Rockwell Automation FactoryTalk Historian SE 3.0 User Manual

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FACTORYTALK HISTORIAN TO HISTORIAN INTERFACE

USER GUIDE

PUBLICATION H2H-UM001A-EN-E–July 2012

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FactoryTalk, Rockwell Automation, Rockwell Software, the Rockwell Software logo are registered trademarks of Rockwell Automation, Inc.

The following logos and products are trademarks of Rockwell Automation, Inc.: FactoryTalk Historian Site Edition (SE), FactoryTalk Historian Machine Edition (ME), RSView, FactoryTalk View, RSView Studio, FactoryTalk ViewStudio, RSView Machine Edition, RSView ME Station, RSLinx Enterprise, FactoryTalk Services Platform, FactoryTalk Live Data, and FactoryTalk VantagePoint.

The following logos and products are trademarks of OSIsoft, Inc.: PI System, Sequencia, Sigmafine, gRecipe, sRecipe, and RLINK.

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Warranty

This product is warranted in accordance with the product license. The product‟s performance may be affected by system

configuration, the application being performed, operator control, maintenance, and other related factors. Rockwell Automation is not responsible for these intervening factors. The instructions in this document do not cover all the details or variations in the equipment, procedure, or process described, nor do they provide directions for meeting every possible contingency during installation, operation, or maintenance. This product‟s implementation may vary among users. This document is current as of the time of release of the product; however, the accompanying software may have changed since the release. Rockwell Automation, Inc. reserves the right to change any information contained in this document or the software at anytime without prior notice. It is your responsibility to obtain the most current information available from Rockwell when installing or using this product.

Chapter 1. Introduction ................................................................................................ 1

Interface Limitations ............................................................................................ 1

Interface Requirements ....................................................................................... 2

Reference Manuals ............................................................................................. 3

Supported Operating Systems ............................................................................ 3

Supported Features............................................................................................. 3

Diagram of Hardware Connection ....................................................................... 7

Chapter 2. Principles of Operation ................................................................ ............ 11

Interface Startup ................................................................................................ 11

How FactoryTalk Historian to Historian Finds Source Points ........................... 12

Data Collection .................................................................................................. 13

History Recovery ............................................................................................... 14

Exception Data Collection ................................................................................. 15

Maximizing Data Throughput .................................................................. 15

Archive Data Collection ..................................................................................... 16

Performance Considerations .................................................................. 16

Data Timestamps .............................................................................................. 17

Data Type Conversions ..................................................................................... 17

Interface Status Events ..................................................................................... 18

Adding, Removing and Editing Tags ................................................................. 18

Error Handling ................................................................................................... 19

Source Historian Server-Level Failover ............................................................ 19

Fault Conditions ................................................................................................ 19

Communication Failure ........................................................................... 19

Detection of Stale Data ........................................................................... 20

UniInt Failover ................................................................................................... 20

Interface Status Tags ........................................................................................ 20

Internal State Status .......................................................................................... 20

Failover Status .................................................................................................. 21

Deployment Scenarios ...................................................................................... 21

Historian to Historian within a Historian Collective ............................................ 21

Tag Attribute Override Parameters ......................................................... 22

Historian to Historian between Historian Collectives .............................. 24

Chapter 3. Installation Checklist ................................................................................ 27

Data Collection Steps ........................................................................................ 27

Interface Diagnostics ......................................................................................... 28

Advanced Interface Features ............................................................................ 29

Chapter 4. Interface Installation ................................................................................. 31

Naming Conventions and Requirements .......................................................... 31

FactoryTalk Historian To Historian Interface User Guide iii

Table of Contents

Interface Directories .......................................................................................... 32

PIHOME Directory Tree .......................................................................... 32

Interface Installation Directory ................................................................ 32

Interface Installation Procedure ........................................................................ 32

Installing Interface as a Windows Service......................................................... 32

Installing Interface Service with Historian Interface Configuration Utility .......... 33

Service Configuration ............................................................................. 33

Installing Interface Service Manually ...................................................... 35

Chapter 5. PointSource .............................................................................................. 37

Chapter 6. Historian Point Configuration .................................................................. 39

Point Attributes .................................................................................................. 39

Tag .......................................................................................................... 39

PointSource ............................................................................................ 40

PointType ................................................................................................ 40

Location1 ................................................................................................ 40

Location2 ................................................................................................ 41

Location3 ................................................................................................ 41

Location4 ................................................................................................ 42

Location5 ................................................................................................ 42

InstrumentTag ......................................................................................... 43

ExDesc .................................................................................................... 43

UserInt1 .................................................................................................. 44

Scan ........................................................................................................ 45

Shutdown ................................................................................................ 45

Exception and Compression ............................................................................. 45

Interface Configurations .......................................................................... 46

Recommended Tag Configurations ........................................................ 46

DataAccess, PtAccess ............................................................................ 47

Zero, Span .............................................................................................. 47

Chapter 7. Interface Status Tag Configuration ......................................................... 49

Chapter 8. Startup Command File ............................................................................. 51

Configuring the interface with ICU .................................................................... 51

FactoryTalk Historian to Historian Interface page .................................. 54

Configuring Interface Startup Files .................................................................... 64

Command-line Parameters ............................................................................... 64

General Interface Operation ................................................................... 65

History Recovery and Archive Data Collection ....................................... 70

Exception Data Collection ....................................................................... 71

Tag Attribute Override ............................................................................ 72

Server-Level Failover .............................................................................. 72

Sample Startup Configuration Files .................................................................. 73

Sample PItoPI.bat File ............................................................................ 73

Sample PItoPI.ini File ............................................................................. 74

Chapter 9. UniInt Failover Configuration .................................................................. 75

Introduction ........................................................................................................ 75

Quick Overview ....................................................................................... 76

Synchronization through a Shared File (Phase 2) ............................................ 77

Configuring Synchronization through a Shared File (Phase 2) ......................... 78

Configuring UniInt Failover through a Shared File (Phase 2) ........................... 81

Start-Up Parameters ............................................................................... 81

Failover Control Points ........................................................................... 83

Historian Tags ......................................................................................... 84

Detailed Explanation of Synchronization through a Shared File (Phase 2) ...... 88

Steady State Operation .......................................................................... 89

Failover Configuration Using ICU ...................................................................... 91

Create the interface Instance with ICU ............................................................. 91

Configuring the UniInt Failover Startup Parameters with ICU .......................... 92

Creating the Failover State Digital State Set .................................................... 92

Using the ICU Utility to create Digital State Set ...................................... 93

Using the SMT 3 Utility to create Digital State Set ................................. 93

Creating the UniInt Failover Control and Failover State Tags (Phase 2) .......... 96

Chapter 10. Interface node Clock ............................................................................ 97

Chapter 11. Security ................................................................................................. 99

Tag and Node Security.................................................................................... 100

System Manager Responsibilities ................................................................... 100

Receiving System Manager .................................................................. 100

Source System Manager ...................................................................... 101

Sample Security Files...................................................................................... 101

Sample 1 ............................................................................................... 101

Sample 2 ............................................................................................... 101

Chapter 12. Starting / Stopping the interface ....................................................... 103

Starting Interface as a Service ........................................................................ 103

Stopping Interface Running as a Service ........................................................ 103

Chapter 13. Buffering ............................................................................................. 105

Which Buffering Application to Use ................................................................. 105

How Buffering Works....................................................................................... 106

Buffering and Historian Server Security .......................................................... 106

Enabling Buffering on an Interface Node with the ICU ................................... 107

Choose Buffer Type .............................................................................. 107

Buffering Settings.................................................................................. 108

Buffered Servers ................................................................................... 110

Installing Buffering as a Service ........................................................... 113

Chapter 14. Interface Diagnostics Configuration ................................................. 117

Scan Class Performance Points ..................................................................... 117

Performance Counters Points ......................................................................... 120

Performance Counters .......................................................................... 121

Performance Counters for both (_Total) and (Scan Class x) ............... 121

Performance Counters for (_Total) only ............................................... 122

Performance Counters for (Scan Class x) only .................................... 125

Interface Health Monitoring Points .................................................................. 126

I/O Rate Point .................................................................................................. 131

Interface Status Point ...................................................................................... 134

FactoryTalk Historian To Historian Interface User Guide v

Table of Contents

Appendix A. Error and Informational Messages ................................................... 137

Message Logs ................................................................................................. 137

Messages ........................................................................................................ 137

Interface Startup Messages ............................................................................ 137

Scan Summary ................................................................................................ 138

System Errors and Historian Errors ................................................................ 138

Historian to Historian Specific Error Messages ............................................... 138

UniInt Failover Specific Error Messages ......................................................... 139

Informational ......................................................................................... 139

Errors (Phase 1 & 2) ............................................................................. 139

Errors (Phase 2) .................................................................................... 141

Appendix B. PI SDK Options .................................................................................. 143

Appendix C. Terminology ...................................................................................... 145

Appendix D. Technical Support and Resources ................................................... 149

Technical Support ........................................................................................... 149

Knowledgebase .................................................................................... 149

Worldwide Support................................................................................ 149

Training Programs ................................................................................ 149

Consulting Services .............................................................................. 150

TechConnect Support ........................................................................... 150

Find the Version and Build Numbers .................................................... 150

View Computer Platform Information .................................................... 150

Appendix E. Revision History ......................................... Error! Bookmark not defined.

Chapter 1. Introduction

The Rockwell FactoryTalk Historian to Historian interface copies tag data from one Historian Server to another. Data is moved in one direction, meaning data is copied from the source to the receiving Historian Server (also referred to as target Historian Server). The interface must run on a Windows Intel-based operating system.

Note: The Rockwell FactoryTalk Historian to Historian interface functions and is configured the same as the standard Rockwell Automation PItoPI interface, with the exception that this interface can only connect to FT Historians.

Interface tags are created on the receiving Historian Server. Each interface tag is configured to receive data for a unique source tag. Tags receive either archive or exception data updates from the source tag. Exception data is data that has not yet been subjected to compression. The type of data collection, exception or archive, is configured through scan class assignment. By default, all tags belonging to the first scan class receive exception data. Tags assigned to any other defined scan class receive archive data.

The interface supports history recovery. History recovery enables users to recover data for time periods when the interface was not running or otherwise unable to collect data. The history recovery period is configurable; the default is 8 hours. Users have the option of performing time-range specific history recovery by specifying a start and end time. In this configuration the interface collects data for the specified time period then exits.

Both source Historian Server-level failover and UniInt Phase 2 interface level failover are supported. When running in source Historian Server-level failover mode, the interface obtains data from one of two available source Historian Servers. The source Historian Servers must have identical tag definitions and data streams for each interface source tag. This requirement ensures the interface will obtain the same data regardless of which source server is active. When running in UniInt Failover mode, two copies of the interface are connected to the source Historian Server at the same time. When the primary interface stops collecting data, the backup interface assumes the primary role and continues data collection. Source Historian Server-level failover and UniInt Phase 2 interface level failover modes can be run simultaneously. Failover maximizes interface data availability on the receiving Historian Server(s).

Interface Limitations

The FactoryTalk Historian to Historian interface is not a true data replication tool. It does not synchronize Historian Server data or perform data validation. It simply provides a method for copying data from one Historian Server to another in an incremental, time forward manner. There is no guarantee that an exact archive data match will exist between the source and receiving Historian Servers. If the goal is to achieve data matching (replication) Rockwell

FactoryTalk Historian To Historian Interface User Guide 1

Introduction

Automation recommends using n-way buffering which is supported with PI API v1.6.x and later. Please see the PI API installation manual for details.

The Historian Archive subsystem may temporarily queue data in memory prior to it being committed to disk. This can lead to data gaps when using Historian to Historian for real-time data collection with history recovery enabled. To avoid data gaps the recommended configuration is to run in history recovery only mode without snapshot updates. Note that this means current real-time data from the source Historian Server will not be available on the target Historian Server.

The interface is a PI API based application. It does not currently support tag annotations, which are only available through the PI SDK. This means it cannot be used to copy Batch Database data between Historian Servers.

The interface is a single threaded process. This design increases performance dependencies on the responsiveness of the source and receiving Historian Servers and dependencies on network quality.

It is highly recommended that users use tools such as Rockwell Automation‟s Performance Monitor interface and Historian Ping interface to monitor these interface dependencies. These interfaces are distributed by default with the latest Historian Server setup kit. This information will be invaluable for troubleshooting Historian to Historian interface issues if they should arise. Using these tools to monitor system health is also part of Rockwell Automation‟s Best Practices Recommendations for FactoryTalk Historian System Mangers.

Interface Requirements

PItoPI requires the following software versions:

 Windows Intel-based operating system  PI API version 1.6.1.5 or greater, which is distributed with the PI SDK installation

kit.

 TCP/IP connections are needed to both receiving and source Historian Servers. This

interface also operates using RAS to connect over dial-up or ISDN connections. Dialup connections of 9600 baud have been used successfully.

 To configure Phase 2 failover using the ICU you must use ICU 1.4.6.0 or later.

Note: The value of [PIHOME] variable for the 32-bit interface will depend on whether the interface is being installed on a 32-bit operating system (C:\Program Files\Rockwell Software\FactoryTalk Historian\PIPC) or a 64-bit operating system (C:\Program Files (x86)\PIPC).

The value of [PIHOME64] variable for a 64-bit interface will be C:\Program Files\Rockwell Software\FactoryTalk Historian\PIPC on the 64-bit Operating system.

In this documentation [PIHOME] will be used to represent the value for either [PIHOME] or [PIHOME64]. The value of [PIHOME] is the directory which is the common location for Historian client applications.

Platforms

32-bit application

64-bit application

Windows XP 32-bit OS

Yes

64-bit OS

Yes (Emulation Mode)

Windows 2003 Server 32-bit OS

Yes

64-bit OS

Yes (Emulation Mode)

Windows 7 32-bit OS

Yes

64-bit OS

Yes (Emulation Mode)

Windows 2008

32-bit OS

Yes

Windows 2008 R2

64-bit OS

Yes (Emulation Mode)

Windows 7 32-bit OS

Yes

64-bit OS

Yes (Emulation Mode)

Feature

Support

Interface Part Number

Historian-IN-RW-FTPI-NTI

* Auto Creates Historian Points

APS Connector

Point Builder Utility

ICU Control

Yes

Historian Point Types

Historian 3: Float16 / Float32 / Float64 / Int16 / Int32 / Digital / String / Blob

Historian 2: R / I / D

Sub-second Timestamps

Yes

Sub-second Scan Classes

Yes

Automatically Incorporates Historian Point Attribute Changes

Yes Exception Reporting

Yes

Outputs from Historian

Reference Manuals

Rockwell Automation

 Historian Server manuals  PI API Installation manual  UniInt Interface User Manual  Historian Interface Status

Supported Operating Systems

The interface is designed to run on the above mentioned Microsoft Windows operating systems and their associated service packs.

Please contact Rockwell Automation Technical Support for more information.

Supported Features

FactoryTalk Historian To Historian Interface User Guide 3

Introduction

Feature

Support

Inputs to Historian: Scan-based / Unsolicited / Event Tags

Scan-based Only * Supports Questionable Bit

Supports Multi-character PointSource

Yes

Maximum Point Count

Unlimited

* Uses PI SDK

PINet String Support

* Source of Timestamps

Source Historian Server

History Recovery

Yes

UniInt-based * Disconnected Startup * SetDeviceStatus

Yes No Yes

Failover

Source Historian Server-Level UniInt Phase 2 Interface Level (Warm)

* Vendor Software Required on Historian interface node / PINet Node

Vendor Software Required on Foreign Device

No Vendor Hardware Required

Additional Historian Software Included with Interface

No Device Point Types

Real, Integer and Digital.

Serial-Based Interface

* See available paragraphs below for further explanation.

APS Connector

The PItoPI APS Connector (PItoPI_APS) is a specific module that communicates with the Receiving and Source Host FactoryTalk Historian SE‟s, gets tag attribute updates from the Source Host FactoryTalk Historian System, and locates new and deleted points on the Source Host FactoryTalk Historian System. The PItoPI APS Connector and its attendant routines are called with each synchronization scan.

Note: The PItoPI APS Connector contains a separate implementation of the procedure to identify the source point for an interface point. If an interface instance is registered with APS, confirm that the PItoPI APS Connector version implements the same procedure as the interface, which is required to ensure that the PItoPI APS Connector synchronizes with the same source point as the interface.

Supports Questionable Bit

The interface will copy questionable bit data for a give source point from one PI3 server to another. However the interface itself does not make this a configurable parameter.

Uses PI SDK

The PI SDK and the PI API are bundled together and must be installed on each interface node. This Interface does not specifically make PI SDK calls.

Maximum Point Count

While the interface does not have a hard-coded point count limit, there are performance dependencies that can effectively limit point count. The interface is a single-threaded process. This design exposes performance dependencies on Historian Server responsiveness and network quality. For example a high latency network connection will result in a significant decrease in data transfer rate over a network connection without high latency.

Source of Timestamps

The source Historian Server provides a timestamp for each data event. Timestamps are automatically adjusted to account for time zone differences if both source and receiving Historian Servers are Historian 3. Time zone adjustment is optional if either Historian Server is Historian 2.

The interface can also adjust timestamps for clock drift. Clock drift is the time offset between Historian Servers after accounting for time zone differences. An offset of 30 minutes or less is considered clock drift. Adjusting for clock drift means the time offset is added to the source timestamp adjusting it to receiving Historian Server time.

Timestamp adjustment is configured on a tag-by-tag basis through the Location2 tag attribute. Note that all computers (interface nodes, source and receiving Historian Servers) must have the correct system time for their configured time zone.

History Recovery

History recovery enables users to recover archive data for time periods when the interface was not running or otherwise unable to collect data. History recovery is performed on startup, after restoring a lost Historian Server connection and after a disruption in exception data collection. In addition, when a new point is added to the interface, history recovery is performed on that point. The history recovery period is configurable. The default is to recover data for the previous 8 hours. History recovery is disabled by setting the time period to 0.

Time range-specific history recovery can be performed by passing a start and end time. When run in this configuration the interface collects data for the specified time range then exits. It should be noted that the start and end time will be relative to the node where the interface runs. This is important if the source Historian Server is in a different time zone than the machine where the interface is running.

UniInt-based

UniInt stands for Universal Interface. UniInt is not a separate product or file; it is an Rockwell Automation-developed template used by developers, and is integrated into many interfaces, including this interface. The purpose of UniInt is to keep a consistent feature set and behavior across as many of Rockwell Automation‟s interfaces as possible. It also allows for the very rapid development of new interfaces. In any UniInt-based interface, the interface uses some of the UniInt-supplied configuration parameters and some interface-specific parameters. UniInt is constantly being upgraded with new options and features.

The UniInt Interface User Manual is a supplement to this manual.

FactoryTalk Historian To Historian Interface User Guide 5

Introduction

SetDeviceStatus

The Historian to Historian Interface is built with UniInt 4.4.4.0. New functionality has been added to support health tags. The Health tag with the point attribute ExDesc =

[UI_DEVSTAT] represents the status of the source device. The following events can be

written into this tag: “1 | Starting” - the interface is starting.

 “Good” - the interface is properly communicating and reading data from the server.  The following event represents a failure to communicate with the server:

o "3 | 1 device(s) in error | Network communication error to source Historian

Server"

o "3 | 1 device(s) in error | Unable to get archive data from source Historian

Server"

o "3 | 1 device(s) in error | Unable to get snapshot data from source Historian

Server"

o "3 | 1 device(s) in error | Unable to write data to receiving Historian Server" o "3 | 1 device(s) in error | Unable to obtain current data with source Historian

Server failover enabled."

 “4 | Intf Shutdown” - the interface is stopped.

Refer to the UniInt Interface User Manual for more information on how to configure health points.

Failover

Source Historian Server-Level Failover Support

Source Historian Server-level failover maximizes interface data availability on the receiving Historian Server(s). It enables the interface to obtain data from one of two source Historian Servers. Each source server must have identical tag definitions and data streams for interface source points. Source Historian Server failover is not supported for Historian 2.

The interface will initiate failover if the active source data becomes stale or is not available due to network issues. The Historian Interface Status utility is required for each source Historian Server to monitor data quality. The interface uses the utility status tag output to verify source data is current and has not become stale.

UniInt Interface Failover Support

UniInt Phase 2 Failover provides support for cold, warm, or hot failover configurations. The Phase 2 hot failover results in a no data loss solution for bi-directional data transfer between the Historian Server and the Data Source given a single point of failure in the system architecture similar to Phase 1. However, in warm and cold failover configurations, you can expect a small period of data loss during a single point of failure transition. This failover solution requires that two copies of the interface be installed on different interface nodes collecting data simultaneously from a single data source. Phase 2 Failover requires each interface have access to a shared data file. Failover operation is automatic and operates with no user interaction. Each interface participating in failover has the ability to monitor and determine liveliness and failover status. To assist in administering system operations, the ability to manually trigger failover to a desired interface is also supported by the failover scheme.

The failover scheme is described in detail in the UniInt Interface User Manual, which is a supplement to this manual. Details for configuring this Interface to use failover are described in the UniInt Failover Configuration section of this manual.

Device Point Types

Real, Integer and Digital.

Diagram of Hardware Connection

The following diagrams illustrate the three basic hardware configurations for PItoPI: the interface runs on the source Historian Server, the interface runs on the receiving Historian Server or the interface runs on a separate interface node. The interface must run on a Windows Intel-based operating system.

Figure 1: Configuration 1 PItoPI runs on the source Historian Server “pushing” data to the receiving Historian Server.

FactoryTalk Historian To Historian Interface User Guide 7

Introduction

Figure 2: Configuration 2 PItoPI runs on the receiving Historian Server “pulling” data from the source Historian Server.

Figure 3: Configuration 3 PItoPI runs on a separate interface node.

FactoryTalk Historian To Historian Interface User Guide 9

Chapter 2. Principles of Operation

The FactoryTalk Historian to Historian interface copies tag data from one Historian Server to another. It consists of a single executable and startup configuration file. No specific tag limit exists for the interface. However, data throughput (events/second) can be limited by network quality and/or system resources on the source and receiving Historian Servers. Users can configure the interface to copy exception (snapshot) or archive data. Although it is possible for one copy of the interface to do both, it is highly recommended that separate copies are used for this purpose to ensure a high level of performance.

Interface Startup

On startup, the interface reads its configuration file for site-specific operating parameters. This file contains required and optional configuration information, such as source and receiving Historian Server, data update rates, and history recovery settings. Next the interface establishes a connection to each Historian Server and initializes its tag lists.

Each client connection to a Historian Server is associated with a specific PI user. This PI user determines what permissions are granted to the client. The source Historian Server must grant the interface permission to read tag attributes and data for interface source tags. On the receiving Historian Server the interface requires read access for tag attributes and read and write data access for its tag list. See the section Tag and Node Security for additional information.

As the interface initializes its tag lists, tags are grouped internally by scan class assignment. Each interface tag must be configured for a unique source tag. If an invalid tag configuration is detected, the tag is either rejected or added to the tag list and marked in error. In either case a message will be logged with specific information about the error. The interface outputs messages to pipc.log, which can be found in the local \pipc\dat directory.

After the interface is finished building its tag lists it calculates the time offset between Historian Servers. The offset is updated every 2 minutes and used for data timestamp adjustments, if configured, and to timestamp interface status events. It is required that each participating node has the correct system time for its configured time zone. At this point the interface is ready to begin data collection.

FactoryTalk Historian To Historian Interface User Guide 11

Principles of Operation

Interface parameters

Search order for attribute containing source point tag name or ID /tn

/tnex

/ptid

1. Non-empty InstrumentTag attribute is source point tag name.

2. ExDesc attribute that contains STAG= specifies source point tag.

3. UserInt1 attribute greater than 0 contains source point ID. (Point rejected if source Historian Server-level failover configured.)

4. Tag of the interface point is also source point tag name.

Yes

UserInt1 attribute contains source point ID. (Illegal configuration if source Historian Server -level failover is configured.)

Yes

1. ExDesc attribute that contains STAG= specifies source point tag.

2. Tag of the interface point is also source point tag name.

Yes

Tag of the interface point is also source point tag name. Yes

N/A

How FactoryTalk Historian to Historian Finds Source Points

When the FactoryTalk Historian to Historian Interface loads a point, the interface must identify the source point from which data will be collected. In other parts of this manual, this process is referred to as mapping the interface point to a source point.

The interface uses four receiving point attributes as possible links to the source point:

InstrumentTag, ExDesc, UserInt1, and Tag. However, the FactoryTalk Historian to

Historian Interface /tn, /tnex, and /ptid parameters exclude one or more of these attributes from mapping to the source point. For most interface instances, none of these parameters are used. The following table summarizes the effect of these parameters on the search for either source point tag name or point ID. The actual implementation of the search is described below the table.

The interface performs the following steps to find the source point:

1. If no /tn parameter and no /tnex parameter and no /ptid parameter and the

InstrumentTag attribute is not a zero-length string, the InstrumentTag value

contains the source tag name and the search ends. Otherwise, proceed to step 2.

2. If no /tn parameter and no /ptid parameter and the ExDesc attribute begins with

case-insensitive “STAG” followed by zero or more spaces followed by “=”, the source tag name is extracted from the remainder of the ExDesc value (as described in the following paragraph) and the search ends. Otherwise, proceed to step 3.

To extract the source tag name, the interface ignores any spaces following the “=”. If the next character is not a double quotation mark ("), it is the first character of the source tag name which extends to the first comma or to the end of the ExDesc attribute. If the first non-space following the “=” is a double quotation mark, the source tag name begins with the following character and extends to the first double quotation mark or to the end of the ExDesc attribute. The interface extracts the source tag name from ExDesc and the search ends.

3. If no /tn parameter and no /tnex parameter and either the UserInt1 attribute is

greater than zero or the /ptid parameter is present, the UserInt1 attribute is the

source point ID and the search ends. Otherwise, proceed to the step 4. If the search ends in this step and either the UserInt1 attribute is not greater than zero or the interface is configured for source Historian Server-level failover, the interface rejects the point.

4. The source point tag name is the same as the receiving tag name.

The search for the source point ends with either a source tag name or source point ID. If the source tag name or point ID does not exist, the interface puts the point into an error state and logs a message.

Note: The PItoPI APS Connector contains a separate implementation of the search for source point tag name or ID. If an interface instance is registered with APS, confirm that the PItoPI APS Connector version implements the same search procedure as the interface, which is required to ensure that the PItoPI APS Connector synchronizes with the same source point as the interface. If the latest release of the PItoPI APS Connector is older than this version of the FactoryTalk Historian to Historian interface, compare the procedure described in this section with

the “How PItoPI and PItoPI_APS Find Source Points” section in the Historian to Historian TCP/IP Interface AutoPointSync Connector user manual.

Data Collection

There are two modes of data collection, history recovery and scanning for updates. History recovery enables users to recover archive data for time periods when the interface was not running or otherwise unable to collect data. After performing history recovery, the interface begins scanning for updates. When the interface is scanning for updates each tag recei Historian to Historian TCP/IP Interface AutoPointSync Connector ves an incremental copy of either archive or exception data from its configured source tag.

A tag configured for exception data receives a copy of its source tag‟s current value updates.

A tag‟s current value is also referred to as its snapshot value. A snapshot value is a data event

that has passed the first level of data filtering, the exception test. Every Historian Server maintains a snapshot table that contains the current value for each tag in its database. When a new value passes exception filtering, the snapshot table is updated. The existing snapshot value is then subjected to the compression test. The compression test determines whether or not a snapshot value is archived. If a value passes compression filtering, it becomes part of the archive data collection.

Tags are configured for archive or exception data collection through scan class assignment. Scan classes are update rates that users define in the interface startup configuration file. When a scan is executed the interface performs an incremental copy of data for each tag in its scan list. By default, all tags assigned to the first scan class receive exception data. Tags assigned to any other scan class receive archive data.

Note: Interface performance is maximized when a separate copy of the interface is used for archive and exception data collection.

All data collected by the interface has already passed exception filtering on the source Historian Server. Any additional exception filtering can only lead to a data mismatch between Historian Servers. Additionally we recommend applying source tag compression deviation settings to interface tags. See the section Exception and Compression for additional information.

FactoryTalk Historian To Historian Interface User Guide 13

Principles of Operation

In general the interface can sustain higher data rates (events/second) when configured for exception data collection. Exception updates are queued in memory on the source Historian Server. This is not the case for archive updates. Only the most recently accessed archive data is stored in memory, specifically the archive data cache. When the interface requests archive data it is likely a certain percentage is read from disk. Disk reads require more computer resources than reading from memory. As the interface data rate increases, the source Historian Server will work harder if the interface is requesting archive versus exception data.

History Recovery

History recovery is executed after each of the following events:

 On interface startup.  After restoring a lost Historian Server connection.  Update overflow error recovery.  For each new point added to the interface.

History recovery is configured through interface startup parameters. Users can specify the recovery period, time increments within the total recovery period, a pause time between increments, and the maximum number of archive events returned per data request. These parameters enable users to manage the performance impact on the source and receiving Historian Servers by throttling the data collection rate.

The starting point for history recovery is set on a tag-by-tag basis. If the current value for a tag is more recent than the starting point of the recovery period, history recovery will begin at

the tag‟s current value. This prevents data overlap, streamlines data retrieval, and prevents

out-of-order data. There is one exception: Pt Created is the value given to a tag when it is created. If the current value of an interface tag is Pt Created, the interface performs history recovery for the total recovery period.

History recovery is performed independently for each scan class. The interface periodically prints a message to indicate completion status. Every minute the interface calculates percent completion. A message will be printed for each 10% completion increment or every 5 minutes, whichever comes first.

If a scan class is configured for exception data collection, the interface transitions from archive to exception data on the last history recovery increment. As the interface cycles through its tag list, each tag is added to the exception update list after obtaining its last recovery increment. By default the interface breaks from history recovery to collect exception updates every 5 seconds. This time interval is configurable through the /rh_qcheck startup parameter. As it nears the end of its tag list, more tags are in the update list and the time to collect exception updates increases. This extra overhead can significantly increase the time for complete history recovery.

The default behavior is for history recovery data to bypass compression on the receiving Historian Server. Source data is written to the receiving archive in one of three modes; append, replace or no replace. This is configured on a tag-by-tag basis. If the /dc interface startup parameter is specified, this data is subjected to compression. Historian 2 and Historian

3.2 servers will always apply compression to interface data. In this case the data write mode is effectively disabled.

Time-range history recovery is configured through the interface startup configuration file. When enabled, the interface starts up, recovers archive data for the specified start and end

time then exits. The times specified are relative to the machine where the interface runs. This is important if the source Historian Server is in a different time zone than the machine where the interface runs. Note that backfilling data may require additional server preparations on the receiving node. For example, there may not be enough space in the target (non-primary) archive for the recovery data, or non-primary archives may not have space allocated for newly created tags. See the Historian Server System Management Guide for information on backfilling data.

Exception Data Collection

Tags assigned to the first scan class receive exception data. An exception is a current value update (snapshot value). On startup each source tag is registered with the update manager on the source FactoryTalk Historian System. The update manager then collects snapshot updates for each registered tag. This data is queued in memory. When the interface executes a scan it requests and processes these events until the queue is empty. Data update latency is minimized by configuring a high frequency scan rate for the exception scan class. Exception and compression should be configured carefully for the interface to avoid data mismatches between Historian Servers. See the section Exception and Compression for additional information.

Maximizing Data Throughput

Interface performance is maximized when a separate copy of the interface is used for archive and exception data collection.

The number of events returned per update request to the source Historian Server is configurable through the interface startup file. The default is for up to 10,000 exception events returned per update request. This list of exceptions is given to the interface in time sequence, oldest to newest. The interface processes the list one event at a time. These events are temporarily queued by the interface. Only one update is queued per tag at any given time. Whenever a second event for any one tag is processed within the exception update list, the interface must first flush its queue, writing this data to the receiving server. This behavior is required for exception data filtering. As a result, the interface will make many more calls writing data to the receiving Historian Server than retrieving data from the source.

Note: Whenever possible, users should run the interface on the receiving Historian Server to minimize the effect of network latency on data throughput.

Network latency will have a significant effect on data throughput. Interface testing over a WAN connection with 200ms latency showed throughput was reduced by 2/3 when the interface ran on the source versus the receiving Historian Server. When run on the receiving Historian Server, the interface was able to sustain 1800 events/second. This was reduced to 600 events/second when the interface ran on the source Historian Server. Testing with a latency of <1 ms, throughput was not affected. The interface maintained 11,000 events/second when run on the source and receiving Historian Server.

FactoryTalk Historian To Historian Interface User Guide 15

Principles of Operation

Archive Data Collection

By default, the first scan class is used for exception data collection. Tags configured for any other scan class will receive archive data. However, exception data collection can be disabled entirely by specifying the /hronly interface startup switch. When specified, all scan classes update with archive data.

When a scan is executed, each tag receives an incremental copy of data. An archive update

begins at the interface tag‟s current value. The source server returns all source tag data

including its current snapshot value. Users have the option of including the current snapshot value with each scan update. This is configured through the Location3 tag attribute. The snapshot value is not part of the archive data collection. Including the snapshot value can lead to a data mismatch between Historian Servers. In this case data compression must be enabled by specifying the /dc startup switch. If this is not done and a tag is configured to include the snapshot, a snapshot value will be archived on each scan. This will result in the interface tag having more archive values than its source.

The default behavior is for archive data collected by the interface to bypass compression on the receiving Historian Server if its version is PI 3.3 or later. Source data is written to the receiving archive in one of three modes; append, replace or no replace. This is configured on a tag by tag basis through the Location5 tag attribute. If the /dc interface startup parameter is specified, this data is subjected to compression which effectively disables the archive write mode. Historian 2 and Historian 3.2 servers will always apply compression to interface data. In this case compression must be managed through interface tag configurations. See the section Exception and Compression for additional information.

Performance Considerations

Load Distribution

Archive data collection can have a significant impact on Historian Server performance. The source server will be providing the interface with outgoing data for its tag list in addition to the normal incoming data rate. This may significantly increase system resource usage. This performance impact can be minimized by distributing tags among multiple scan classes.

For example, a user configures the interface for 10,000 tags. Instead of assigning these tags to a single scan class, multiple scan classes are used. The user defines ten scan classes and assigns 1,000 tags to each one. A 10-minute update rate is chosen with each scan class offset by one minute. The result is each scan executes one minute after the next distributing the 10,000 tag updates into 10 requests of 1,000 tags each. When compared to having all tags belong to one scan class, this configuration is a more efficient use of server resources.

Scan Rates

The scan class update frequency can be chosen to minimize the performance impact on the source Historian Server. Recent archive data is cached in Historian Server memory for each tag. Historian Server resource usage is minimized when interface updates are obtained by reading cached data. If the data does not reside in memory it is read from disk. Disk reads require more hardware resources than a memory read. When possible a scan frequency should be chosen that minimizes disk access while maximizing the time between scans.

A Historian 3.4 server allocates space for 4 data events per point in the archive read memory cache. This cache size is a configurable parameter. When the interface performs history

Receiving Tag Point Type

Source

Tag Point

Type

Float 16/32/64

Int16/32

Digital

String Float 16/32/64

Yes

recovery nearly all data is obtained from disk reads. When the interface transitions to scanning for updates, disk reads should decrease as recent data is obtained from the archive memory cache. The percentage of data obtained via disk reads versus memory can be managed through the scan frequency. Increasing the scan rate should increase the percentage read from memory. Vice versa, decreasing the scan rate increases the percentages of data obtained from disk reads. With some trial and error users can determine a scan rate that maximizes the time between scans while minimizing archive disk reads. For Historian 3 source servers, use the Historian Performance Monitor interface to access archive cache versus disk read data counters. Historian 2 source servers will want to monitor disk versus cache read ratios.

Data Timestamps

The source Historian Server provides a timestamp for each data event. These timestamps may be adjusted to account for time zone differences and clock drift between Historian Servers. It is required that each Historian Server have the correct system time for the configured time zone.

Timestamps are automatically adjusted for time zone differences when both source and receiving servers are PI3. PI3 uses Universal Coordinated Time (UTC) to timestamp data. UTC is based on seconds since Jan.1, 1970 in Greenwich Mean Time. Each UTC time stamp contains a time offset from Greenwich Mean Time that represents the local time zone setting.

If source and/or receiving Historian Server is PI2, users have the option of adjusting for time zone differences. PI2 uses local time. Local time is seconds since Jan. 1, 1970 in the local time zone. PI2 data timestamps do not include a time zone offset. For example, viewing data from a PI2 server in a time zone two hours behind your local time will appear to be two hours old. PI3 data includes time zone information that allows for automatic adjustment to local time.

The interface can also adjust for clock drift between Historian Servers. Clock drift is the time offset between Historian Servers after accounting for time zone differences. An offset of 30 minutes or less is considered clock drift. When configured to do so, the time offset is added to the timestamp provided by the source Historian Server adjusting it to receiving Historian Server time.

Timestamp adjustment is configured on a tag-by-tag basis through the Location2 tag attribute. Note that all computers (interface node, source and receiving Historian Server) must have the correct system time for the configured time zone.

Data Type Conversions

The following table displays supported data type conversions between source and receiving Historian tags.

FactoryTalk Historian To Historian Interface User Guide 17

Principles of Operation

Int16/32

Yes Yes

Digital

Yes No

String

Yes

Interface Status Events

The FactoryTalk Historian to Historian interface may update a tag to indicate a specific status event. These status events represent data that is generated by the interface and therefore will not exist for the source tag.

There are three specific status events generated by the interface:

 IO Timeout status events are triggered when the interface loses a Historian Server

connection. This information informs users that current data is not being collected. An event is written to indicate the time of disconnection and another event is written to indicate the time of reconnection.

 Access Denied status events are written whenever the interface is denied access to a

tag‟s data or attribute information.

 Intf Shut status events are enabled through /stopstat startup parameter. When

enabled an event is written when the interface is stopped and again on startup. These events tell users no data is being collected because the interface is not running. See a more detailed description in the “Command-line Parameters” section.

To prevent a data mismatch between Historian Servers these status events should be disabled. If enabled these events create a data gap that will not be filled through history recovery.

Each tag receives an „IO Timeout‟ event at the time of Historian Server disconnection and a second event at reconnection. Likewise, when the interface is stopped and started a

„Shutdown‟ event is written to each tag. History recovery begins either at the start of the

recovery period or a tag‟s current value, whichever is more recent. The status events are

updated prior to performing history recovery, making them the starting point of the recovery period for each tag. This results in a gap in data for a time period that might otherwise be recovered.

Interface status events are configured on a tag-by-tag basis through the Location3 tag attribute. Interface shutdown events are enabled through the interface startup script. By default shutdown events are not written by the interface.

Adding, Removing and Editing Tags

Tag definitions can be modified while the interface is running. The interface periodically checks with the receiving Historian Server for tag configuration updates. These updates include adding, editing, and removing tags. During normal operation the interface checks for updates every two minutes. It will only process up to 25 tag updates on any given update. This is to prevent the processing of tag updates from delaying data collection. If there are more than 25 tag updates, the interface will check again every 30 seconds until all updates have been processed. Processing tag updates is a low priority for the interface. If a large

number of tag edits are made, a user may choose to restart the interface. Restarting the interface will force it to process all edits by rebuilding its tag list.

Error Handling

When the interface encounters an error, it will print a message to the log file. If the error is tag-specific, the error message will include the tag name along with the specific error code. The tag is then marked by the interface as being in error and removed from the update list. The interface will attempt to clear tags in error every 10 minutes. It does this by trying to read a value from the source tag and then update the interface tag with that value. If this is successful, the tag is added back to its assigned scan class for data collection. Otherwise, it remains in error until the next attempt to clear it.

If an error is not tag-specific, the interface verifies server connectivity. Typically system errors are a result of network upsets. When a system error is encountered, the interface verifies Historian Server communication and attempts to continue collecting data.

Source Historian Server-Level Failover

Source Historian Server-level failover maximizes interface data availability on the receiving Historian Server. It requires that two Historian source servers are available that have identical tag definitions and data streams for interface points. This requirement ensures the interface will obtain the same data regardless of which source server is active. Source Historian Serverlevel failover is not supported for Historian 2.

Failover is enabled by specifying a primary and secondary source server in the interface startup file. On startup the interface attempts to establish a connection to each source server then load and initialize its tag list. Data collection begins from the primary source server making it the active node while the secondary source server assumes the standby role. However, if one of the source servers is unavailable on startup, the other server is designated the active source regardless of primary or secondary configuration.

Note: Source tag mapping by point ID is not compatible with server-level failover. This is because there is no guarantee of a point ID match between two source Historian Servers unless they are part of a Historian Collective.

Fault Conditions

There are two conditions that will cause the interface to initiate failover: a communication failure or detection of stale data.

Communication Failure

The first failover condition is when the interface loses communication to the active Historian source server. This may be the result of a temporary network upset, shutdown of the active source server, hardware failure, etc. The interface has no way of identifying what causes the disconnection. A disconnection means the interface did not receive a response from the active source within the timeout period. The interface may initiate a short wait then attempt to reconnect to the active source before attempting to failover. The timeout period, pause

FactoryTalk Historian To Historian Interface User Guide 19

Principles of Operation

between reconnection, and number of reconnection attempts are all user configurable parameters.

Note: the default network timeout period is 60 seconds. This is not an interface configuration parameter. This is configured through the PI API configuration file, pilogin.ini. Please refer to the PI API Users Manual for information on adjusting the default timeout period.

Detection of Stale Data

The second failover condition is stale source data. The Historian Interface Status Utility is required on each source server to track data quality. This utility is a separate program that monitors updates to a specified watchdog tag. The utility updates a status tag to indicate whether or not the watchdog tag is being updated. The interface monitors this status tag as an indicator that source data is current. When configuring the Interface Status Utility users will want to select a watchdog tag that receives reliable high frequency updates.

Whenever possible the interface is connected to a source Historian Server that is actively receiving data. If this is not possible, the interface enters a loop where it waits for the first available source Historian Server receiving data.

Note: The Historian Interface Status Utility is not included as part of the interface installation. It is available for downloaded on our website;

http://support.rockwellautomation.com

UniInt Failover

This interface supports UniInt Phase 2 failover with warm failover configuration. Refer to section UniInt Failover Configuration of this document for configuring the interface for failover.

Interface Status Tags

The interface has the optional functionality of outputting status data to a digital tag. There are two optional status tags that are mutually exclusive. These are digital tags that are created on the receiving Historian Server. These tags are useful for tracking performance and assisting with troubleshooting.

Internal State Status

The interface updates the internal state tag to indicate when it executes specific functions. Specifically, the status will indicate whether the interface is in startup, performing history recovery, scanning for data, experiencing network communication errors, denied data or point access (security permissions) or performing shutdown operations. This functionality is enabled by specifying an internal state status tag in the interface startup script.

Failover Status

When configured for server-level failover users can specify a status tag. The interface will update this tag to indicate whether the primary or secondary source server is active. It will also update this tag when it is in the process of failing over (no active source) or experiencing network communication errors.

Deployment Scenarios

There are two typical FactoryTalk Historian to Historian interface applications. One is to isolate users from the source Historian Server. This may be for security requirements, load distribution, database centralization or to resolve remote access issues. In this scenario users will want to configure the interface for exception data collection to provide real-time updates to end users.

The other application is to maintain a copy of archive data on a secondary Historian Server. For example, in this scenario the receiving Historian Server maybe a backup of the source Historian Server. This is achieved by running the interface in archive data collection mode with tag attribute overrides in the startup configuration file. The tag attribute overrides enable users to configure interface data collection without configuring receiving tags specifically for PItoPI. This strategy allows receiving tags to be configured for their native interfaces and eliminates the need for mass tag editing prior to bringing the backup server online, reducing down time.

Historian to Historian within a Historian Collective

PItoPI can be used to distribute data within a collective. The primary method for data distribution within a collective is n-way data buffering from the data source. N-way data buffering provides the best performance and is the most efficient method for data distribution. However due to system architecture and security restrictions this may not always be possible.

FactoryTalk Historian To Historian Interface User Guide 21

Principles of Operation

Historian to Historian is used to transfer data within a collective when the data cannot be sent directly from the interface node. The following section describes typical configuration and deployment scenarios when running Historian to Historian within a collective.

Tag Attribute Override Parameters

The interface supports tag attribute override parameters. These startup parameters must be used when running the interface within a collective. Tag attribute override parameters enable the interface to collect data for tags that are not actually configured for the Historian to Historian interface.

Each member of a collective is required to have identical Historian point database definitions. Using Historian to Historian within a collective will result in the need to have a tag configured for Historian to Historian on one collective member but these same tags must also be configured for the native data source interface on a different collective member.

For example, consider a secondary Historian Collective node that sits behind a firewall. The primary Historian Collective node receives data directly from a Historian OPC and a Historian ModBus interface node. The points on the secondary Historian Collective node are defined exactly as they are on the primary Historian Collective node. This means these points are either configured for the Historian OPC or the Historian ModBus interface

Example Architecture for Historian to Historian within a Historian Collective

Tag attribute override parameters allow users to pass global settings that enable the interface to identify and build its tag list without requiring the tags to be defined explicitly for Historian to Historian. A detailed description of the tag attribute override parameters can be found in section Startup Command File section of this manual.

Firewall Considerations

When a firewall separates the source and receiving Historian Servers for the Historian to Historian interface users may want to run the interface outside of the firewall network. This configuration requires that port 5450 be opened for incoming connections to the Historian Server through the firewall. All outgoing connections from the Historian Server will require that port 1024+ and greater are opened. Additional configuration information for implementing a firewall can be found in our knowledge base (KB) article #2820OSI8 which is available on our TechSupport website (http://support.rockwellautomation.com).

For the best security posture, Historian to Historian should push data out from the most sensitive Historian Server. Enable buffering to eliminate the latency bottleneck.

FactoryTalk Historian To Historian Interface User Guide 23

Principles of Operation

Historian to Historian between Historian Collectives

The following diagram architecture depicts a typical deployment of Historian to Historian for aggregating data between two Historian Collectives.

Limitations

The following limitations apply to the Historian to Historian interface when aggregating data between two collectives.

Historian Collective Support

The Historian to Historian interface is not collective aware. While multiple Historian Servers will compose a collective, the interface will only know about the Historian Servers specified in its startup file. This means on startup both receiving and source Historian Server(s) specified in the interface startup file must be available in order for the interface to initialize its point list.

After the interface is up and running, and if n-way buffering is enabled, the interface will collect data even if the receiving Historian Server is not available. This means data flow is not dependent on the receiving Historian Server once the interface has completed is startup initializations.

Be aware that history recovery can be compromised when the interface is configured for nway buffering to a collective. On startup the interface will check the snapshot value on the receiving Historian Server for each tag in its tag list. The snapshot value is used to determine the starting point for history recovery. This snapshot check only occurs on the receiving Historian Server specified in the interface startup file. Therefore if the last value for each tag assigned to the interface is not the same among Historian Servers in the receiving collective, it will result in either a data gap or data overlap. The best way to avoid this scenario is to initialize all Historian Servers in the receiving collective with the same set of data for the interface tag list prior to implementing the Historian to Historian interface.

Note: The Buffer Subsystem v3.4.375.38 only supports writing to the archive in NO REPLACE mode. This prevents the Historian to Historian interface from honoring Location5 archive write options and can lead to data loss. It is recommended users use a later version of Buffer Subsystem or Historian Bufserv to avoid this issue. Please check our support website for the latest versions;

http://support.rockwellautomation.com

Data Latency and Source Historian Server Failover

The source Historian Server (or source Historian Server pair if failover is enabled) should receive data directly from the interface node populating data for the Historian to Historian source tag list. Not only will this ensure a seamless data transition on failover, it will also minimize data latency to the receiving Historian Server(s). In this context data latency is the time it takes between obtaining a value at the data source and having it arrive at the receiving Historian Server via the Historian to Historian interface.

UniInt Failover

This interface supports UniInt failover. Refer to the UniInt Failover Configuration section of this document for configuring the interface for failover.

FactoryTalk Historian To Historian Interface User Guide 25

Chapter 3. Installation Checklist

If you are familiar with running FactoryTalk Historian data collection interface programs, this checklist helps you get the interface running. If you are not familiar with Historian Interfaces, return to this section after reading the rest of the manual in detail.

This checklist summarizes the steps for installing this Interface. You need not perform a given task if you have already done so as part of the installation of another interface. For example, you only have to configure one instance of Buffering for every interface node regardless of how many interfaces run on that node.

The Data Collection Steps below are required. Interface Diagnostics and Advanced Interface Features are optional.

Data Collection Steps

1. Confirm that you can use SMT to configure the Historian Server. You need not run

SMT on the same computer on which you run this Interface.

2. If you are running the interface on an interface node, edit the Historian Server‟s Trust

Table to allow the interface to write data.

3. Run the installation kit for the Historian Interface Configuration Utility (ICU) on the

interface node if the ICU will be used to configure the interface. This kit runs the PI SDK installation kit, which installs both the PI API and the PI SDK.

4. Run the installation kit for this Interface. This kit also runs the PI SDK installation kit

which installs both the PI API and the PI SDK if necessary.

5. If you are running the interface on an interface node, check the computer‟s time zone

properties. An improper time zone configuration can cause the Historian Server to reject the data that this Interface writes.

6. Run the ICU and configure a new instance of this Interface. Essential startup

parameters for this Interface are

Point Source (/PS=x) Interface ID (/ID=#) Historian Server (/Host=host:port) Scan Class(/F=##:##:##,offset)

7. If you will use digital points, define the appropriate digital state sets on receiving

node. These should correspond to digital state sets assigned to source tags.

8. Choose a point source. If Historian 2 home node, create the point source.

FactoryTalk Historian To Historian Interface User Guide 27

Installation Checklist

9. Build input tags and, if desired, output tags for this Interface. Important point

attributes and their use are:

Location1 specifies the interface instance ID Location2 specifies for timestamp adjustment. Location3 specifies for configuring interface status events. Location4 specifies the scan class. Location5 sets the write mode of archived data on the receiving Historian Server. InstrumentTag specifies the name of the Source Tag from the Source Historian

Server.

ExDesc is an alternative way to specify the Source Tag. This can be specified with STAG=<tagname>. UserInt1 defines Source Tag point ID instead of using source tag name.

10. Start the interface interactively and confirm its successful connection to the Historian

Server without buffering.

11. Confirm that the interface collects data successfully.

12. Stop the interface and configure a buffering application (either Bufserv or PIBufss).

When configuring buffering use the ICU menu item Tools  Buffering…  Buffering Settings to make a change to the default value (32678) for the Primary and Secondary Memory Buffer Size (Bytes) to 2000000. This will optimize the throughput for buffering and is recommended by OSIsoft.

13. Start the buffering application and the interface. Confirm that the interface works

together with the buffering application by either physically removing the connection between the interface node and the Historian Server Node or by stopping the Historian Server.

14. Configure the interface to run as a Service. Confirm that the interface runs properly

as a Service.

15. Restart the interface node and confirm that the interface and the buffering application

restart.

Interface Diagnostics

1. Configure Scan Class Performance points.

2. Install the Historian Performance Monitor Interface (Full Version only) on the

interface node.

3. Configure Performance Counter points.

4. Configure UniInt Health Monitoring points

5. Configure the I/O Rate point.

6. Install and configure the Interface Status Utility on the Historian Server Node.

7. Configure the Interface Status point.

Advanced Interface Features

Configure UniInt Failover; see that section in this document for details related to configuring the interface for failover.

FactoryTalk Historian To Historian Interface User Guide 29

Chapter 4. Interface Installation

Rockwell Automation recommends that interfaces be installed on interface nodes instead of directly on the Historian Server node. An interface node is any node other than the Historian Server node where the FactoryTalk Historian application Programming Interface (PI API) has been installed (see the PI API manual). With this approach, the Historian Server need not compete with interfaces for the machine‟s resources. The primary function of the Historian Server is to archive data and to service clients that request data.

After the interface has been installed and tested, Buffering should be enabled on the interface node. Buffering refers to either PI API Buffer Server (Bufserv) or the PI Buffer Subsystem (PIBufss). For more information about Buffering see the Buffering section of this manual.

In most cases, interfaces on interface nodes should be installed as automatic services. Services keep running after the user logs off. Automatic services automatically restart when the computer is restarted, which is useful in the event of a power failure.

The guidelines are different if an interface is installed on the Historian Server node. In this case, the typical procedure is to install the Historian Server as an automatic service and install the interface as an automatic service that depends on the PI Update Manager and PI Network Manager services. This typical scenario assumes that Buffering is not enabled on the Historian Server node. Bufserv can be enabled on the Historian Server node so that interfaces on the Historian Server node do not need to be started and stopped in conjunction with Historian, but it is not standard practice to enable buffering on the Historian Server node. The Buffer Subsystem can also be installed on the Historian Server. See the UniInt Interface User Manual for special procedural information.

Naming Conventions and Requirements

In the installation procedure below, it is assumed that the name of the interface executable is

PItoPI.exe and that the startup command file is called PItoPI.bat.

When Configuring the interface Manually

It is customary for the user to rename the executable and the startup command file when multiple copies of the interface are run. For example, PItoPI1.exe and PItoPI1.bat would typically be used for interface number 1, PItoPI2.exe and PItoPI2.bat for interface number 2, and so on. When an interface is run as a service, the executable and the command file must have the same root name because the service looks for its command-line parameters in a file that has the same root name.

FactoryTalk Historian To Historian Interface User Guide 31

Interface Installation

Interface Directories

PIHOME Directory Tree

The [PIHOME] directory tree is defined by the PIHOME entry in the pipc.ini configuration file. This pipc.ini file is an ASCII text file, which is located in the %windir% directory.

For 32-bit operating systems a typical pipc.ini file contains the following lines:

[PIPC] PIHOME=C:\Program Files\Rockwell Software\FactoryTalk

Historian\PIPC

For 64-bit operating systems a typical pipc.ini file contains the following lines:

[PIPC]

PIHOME=C:\Program Files (X86)\PIPC

The above lines define the root of the PIHOME directory on the C: drive. The PIHOME directory does not need to be on the C: drive. Rockwell Automation recommends using the paths shown above as the root PIHOME directory name.

Interface Installation Directory

The interface install kit will automatically install the interface to:

PIHOME\Interfaces\ PItoPI\ PIHOME is defined in the pipc.ini file.

Note: All FactoryTalk Historian to Historian interface files are installed into

PIHOME\Interfaces\PItoPI. If multiple copies of the interface are already installed with names other than PItoPI, they will not be upgraded. Upgrade of multiple interfaces should be done by manually copying the executable files and startup files.

Interface Installation Procedure

The FactoryTalk Historian to Historian Interface setup program uses the services of the Microsoft Windows Installer. Windows Installer is a standard part of Windows 2000 and greater operating systems. To install, run the appropriate installation kit.

PItoPI_#.#.#.#_.exe

Installing Interface as a Windows Service

The FactoryTalk Historian to Historian Interface service can be created, preferably, with the Historian Interface Configuration Utility, or can be created manually.

Installing Interface Service with Historian Interface Configuration Utility

The Historian Interface Configuration Utility provides a user interface for creating, editing, and deleting the interface service:

Service Configuration

Service name

The Service name box shows the name of the current interface service. This service name is obtained from the interface executable.

This is the service ID used to distinguish multiple instances of the same interface using the same executable.

Display name

The Display Name text box shows the current Display Name of the interface service. If there is currently no service for the selected interface, the default Display Name is the service name with a “Historian-” prefix. Users may specify a different Display Name. Rockwell Automation suggests that the prefix “Historian-” be appended to the beginning of the interface to indicate that the service is part of the Rockwell Automation suite of products.

FactoryTalk Historian To Historian Interface User Guide 33

Interface Installation

Log on as

The Log on as text box shows the current “Log on as” Windows User Account of the interface service. If the service is configured to use the Local System account, the Log on as text box will show “LocalSystem.” Users may specify a different Windows User account for the service to use.

Password

If a Windows User account is entered in the Log on as text box, then a password must be provided in the Password text box, unless the account requires no password.

Confirm password

If a password is entered in the Password text box, then it must be confirmed in the Confirm Password text box.

Dependencies

The Installed services list is a list of the services currently installed on this machine. Services upon which this interface is dependent should be moved into the Dependencies list using the

button. For example, if API Buffering is running, then “bufserv” should be selected

from the list at the right and added to the list on the left. To remove a service from the list of dependencies, use the button, and the service name will be removed from the

Dependencies list. When the interface is started (as a service), the services listed in the dependency list will be

verified as running (or an attempt will be made to start them). If the dependent service(s) cannot be started for any reason, then the interface service will not run.

Note: Please see the Historian Log and Windows Event Logger for messages that may indicate the cause for any service not running as expected.

- Add Button

To add a dependency from the list of Installed services, select the dependency name, and click the Add button.

- Remove Button

To remove a selected dependency, highlight the service name in the Dependencies list, and click the Remove button.

The full name of the service selected in the Installed services list is displayed below the Installed services list box.

Startup Type

The Startup Type indicates whether the interface service will start automatically or needs to be started manually on reboot.

Windows Service Installation Commands on an interface node or a Historian Server Node with Bufserv implemented

Manual service

PItoPI.exe -install -depend "tcpip bufserv"

Automatic service

PItoPI.exe -install -auto -depend "tcpip bufserv"

*Automatic service with service ID

PItoPI.exe -serviceid X -install -auto -depend "tcpip bufserv"

Status of

Service

Status of the

 If the Auto option is selected, the service will be installed to start automatically when

the machine reboots.

 If the Manual option is selected, the interface service will not start on reboot, but will

require someone to manually start the service.

 If the Disabled option is selected, the service will not start at all.

Generally, interface services are set to start automatically.

Create

The Create button adds the displayed service with the specified Dependencies and with the specified Startup Type.

Remove

The Remove button removes the displayed service. If the service is not currently installed, or if the service is currently running, this button will be grayed out.

Start or Stop Service

The toolbar contains a Start button and a Stop button . If this interface service is not currently installed, these buttons will remain grayed out until the service is added. If this interface service is running, the Stop button is available. If this service is not running, the Start button is available.

The status of the interface service is indicated in the lower portion of the ICU dialog.

the ICU

Interface Service

installed or uninstalled

Installing Interface Service Manually

Help for installing the interface as a service is available at any time with the command:

PItoPI.exe -help

Open a Windows command prompt window and change to the directory where the

PItoPI1.exe executable is located. Then, consult the following table to determine the

appropriate service installation command.

FactoryTalk Historian To Historian Interface User Guide 35

Interface Installation

Windows Service Installation Commands on an interface node or a Historian Server Node without Bufserv implemented

Manual service

PItoPI.exe -install -depend tcpip

Automatic service

PItoPI.exe -install -auto -depend tcpip

*Automatic service with service ID

PItoPI.exe -serviceid X -install -auto -depend tcpip

*When specifying service ID, the user must include an ID number. It is suggested that this number correspond to the interface ID (/id) parameter found in the interface .bat file.

Check the Microsoft Windows Services control panel to verify that the service was added successfully. The services control panel can be used at any time to change the interface from an automatic service to a manual service or vice versa.

Chapter 5. PointSource

The PointSource is a unique, single or multi-character string that is used to identify the Historian point as a point that belongs to a particular interface. For example, the string Boiler1 may be used to identify points that belong to the MyInt Interface. To implement this, the PointSource attribute would be set to Boiler1 for every Historian Point that is configured for the MyInt Interface. Then, if /ps=Boiler1 is used on the startup command- line of the MyInt Interface, the interface will search the Historian Point Database upon startup for every Historian point that is configured with a PointSource of Boiler1. Before an interface loads a point, the interface usually performs further checks by examining additional Historian Point Attributes to determine whether a particular point is valid for the interface. For additional information, see the /ps parameter. If the PI API version being used is prior to

1.6.x or the Historian Server version is prior to 2.x, the PointSource is limited to a single character unless the SDK is being used.

Case-sensitivity for PointSource Attribute

The PointSource character that is supplied with the /ps command-line parameter is not case sensitive. That is, /ps=P and /ps=p are equivalent.

FactoryTalk Historian To Historian Interface User Guide 37

PI API

Historian Server

Maximum Length

1.6.0.2 or higher

2.x or higher

1023

1.6.0.2 or higher

Below 2.x

255

Below 1.6.0.2

2.x or higher

255

Below 1.6.0.2

Below 2.x

255

Chapter 6. Historian Point Configuration

The Historian point is the basic building block for controlling data flow to and from the Historian Server. A single point is configured for each measurement value that needs to be archived.

The following tag attributes are used for defining interface points on the receiving Historian Server.

Point Attributes

Use the point attributes below to define the Historian point configuration for the interface, including specifically what data to transfer.

Tag

The Tag attribute (or tagname) is the name for a point. There is a one-to-one correspondence between the name of a point and the point itself. Because of this relationship, FactoryTalk Historian documentation uses the terms “tag” and “point” interchangeably.

Follow these rules for naming Historian Points:

 The name must be unique on the Historian Server.  The first character must be alphanumeric, the underscore (_), or the percent sign (%).  Control characters such as linefeeds or tabs are illegal.  The following characters also are illegal: * ‟ ? ; { } [ ] | \ ` „ “

Length

Depending on the version of the PI API and the Historian Server, this Interface supports tags whose length is at most 255 or 1023 characters. The following table indicates the maximum length of this attribute for all the different combinations of PI API and Historian Server versions.

FactoryTalk Historian To Historian Interface User Guide 39

If the Historian Server version is earlier than 2.x or the PI API version is earlier than 1.6.0.2, and you want to use a maximum tag length of 1023, you need to enable the PI SDK. See

Appendix_B for information.

Historian Point Configuration

The Historian 2 tag name attribute LongName is used if it exists. The receiving and source tag names do not need to be identical. However, unless the

receiving tag attributes InstrumentTag or ExDesc specify the source tag name or the

/ptid interface parameter is used, the receiving tag name is assumed to be the same as the

source tag name. The How PItoPI Finds Source Points section explains how the interface parameters affect which receiving tag attributes are used for mapping to the source point and the order that the attributes are searched for a mapping.

Note: If the source tag name length exceeds 80 characters, users must use the UserInt1 attribute for source point mapping. This is due to a limitation with the PI API programming library which supports tag names of 80 characters or less for point ID resolution.

PointSource

The PointSource is a unique, single or multi-character string that is used to identify the Historian point as a point that belongs to a particular interface. For additional information, see the /ps command-line parameter and the “PointSource” section.

PointType

The interface supports all Historian point types. Historian 2 point types are R (float16 and float32), D (digital) and I (int16). Historian 3 point types are float16, float32, float64, int16, int32, digital, timestamp, string, and blobs. For more information on the individual PointTypes, see Historian Server manuals.

Users should configure interface tags to be the same PointType as their source tag to maintain data consistency between Historian Servers. If interface tags have different PointType from their source tags, the interface will perform point type conversion. Refer to section Data Type

Conversion of this document.

Location1

Location1 indicates to which copy of the interface the point belongs. The value of this

attribute must match the /id startup parameter. In some cases users may run multiple copies of the interface that share the same point source.

Each instance of the interface is differentiated by its interface ID. The Location1 tag attribute defines which copy of the interface a tag is assigned to.

Location2 Value

Adjust for Time Zone Differences

Do Not Adjust for Time Zone Differences*

Adjust for Clock Drift**

Truncate Sub-Second Timestamps***

Yes - --

Yes

-- 3 --

Yes

Yes 5 --

Yes

* Only available if source and/or receiving Historian Server is a PI2 system. ** Receiving Historian Server is the time master. Timestamps are adjusted to receiving Historian

Server time. An offset of 30 minutes or less is considered clock drift. ***Truncating sub-second timestamps can lead to data loss during history recovery and archive data

scanning if multiple events are stored within the same second. Use with caution.

Location3 Value

Write “I/O Timeout”

Write “Access Denied”

Include Snapshot

Point Level Debugging

Yes

-- 1 --

Yes

-- 3 --

Yes

-- 5 --

Yes

-- 7 --

Yes

Yes 9 --

Yes

Location2

Location2 specifies data timestamp adjustment. The source Historian Server supplies a

timestamp for each data event. Users have the option of adjusting these timestamps to account for time differences between Historian Servers. It is required that each Historian Server have the correct system time for its configured time zone. See section Data

Timestamps for a complete discussion.

Location3

Location3 is used to configure what interface status events are written to a tag.

„IO Timeout‟ status events will result in a data gap for periods of Historian Server disconnection. See section Interface Status Events for a complete discussion.

If a tag is configured for archive data collection, this attribute also specifies whether or not the snapshot value is included with each scan update.

FactoryTalk Historian To Historian Interface User Guide 41

Historian Point Configuration

Location3 Value

Write “I/O Timeout”

Write “Access Denied”

Include Snapshot

Point Level Debugging

Yes

Location5

Write Mode

Description

Supported Historian Server versions

ARCAPPEND

Archive and Snapshot Data

Add archive event regardless of existing events.

Default snapshot behavior is to append data if event at timestamp exists..

PI3 only*

ARCNOREPLACE

Archive Events Only

Add archive event unless event(s) exist at same time.

Default snapshot behavior is to append data if event at timestamp exists.

PI2 only

ARCREPLACE

Archive Events Only

Add archive event, replace if event at same time.

Default snapshot behavior is to append data if event at timestamp exists.

PI3 & PI2

ARCNOREPLACE

Archive and Snapshot Events

Add archive or snapshot event unless event(s) exist at same time

PI2 only

ARCREPLACE

Archive and Snapshot Events

Add archive or snapshot event, replace if event at same time

PI3 & PI2

*Note: PI2 supports Insert (ARCNOREPLACE) or Replace (ARCREPLACE) data write

Location4

Scan-based Inputs

For interfaces that support scan-based collection of data, Location4 defines the scan class for the Historian point. The scan class determines the frequency at which input points are scanned for new values. For more information, see the description of the /f parameter in the

Startup Command File section.

Location5

Location5 attribute is used for setting the write mode for sending archive data to the

receiving Historian Server. The following table lists the supported modes for PI3 and PI2 receiving Historian Servers.

modes. It is not possible for PI2 to have two values with the same timestamp.

PI API

Historian Server

Maximum Length

1.6.0.2 or higher

2.x or higher

1023

1.6.0.2 or higher

Below 2.x

Below 1.6.0.2

2.x or higher

Below 1.6.0.2

Below 2.x

InstrumentTag

Note: If the source tag name length exceeds 80 characters, users must use the

UserInt1 attribute for source point mapping. This is due to a limitation with the PI API programming library which supports tag names of 80 characters or less for point ID resolution.

Length

Depending on the version of the PI API and the Historian Server, this Interface supports an

InstrumentTag attribute whose length is at most 32 or 1023 characters. The following table

indicates the maximum length of this attribute for all the different combinations of PI API and Historian Server versions.

If the Historian Server version is earlier than 2.x or the PI API version is earlier than 1.6.0.2, and you want to use a maximum InstrumentTag length of 1023, you need to enable the PI SDK. See Appendix B for information.

Unless the /tn, /tnex, or /ptid interface parameter is used, the InstrumentTag can be used to specify the source tag. The ExDesc and Tag attributes can also be used for source tag name definition. The UserInt1 attribute can be used to specify source tag by point ID instead of tag name. The How PItoPI Finds Source Points section explains how the interface parameters affect which receiving tag attributes are used for mapping to the source point and the order that the attributes are searched for a mapping.

The interface checks the InstrumentTag attribute first. If the InstrumentTag is empty, the extended descriptor is checked for STAG=<tagname> at the beginning of the ExDesc value. That is, the ExDesc attribute must begin with the „STAG‟ keyword. If neither

InstrumentTag nor ExDesc has a tag name, the UserInt1 attribute is checked for the

source tag point ID. Finally if none of these three attributes identify a source point, the receiving tag name is used for the source tag name.

ExDesc

Note: If the source tag name length exceeds 80 characters, users must use the

UserInt1 attribute for source point mapping. This is due to a limitation with the PI API programming library which supports tag names of 80 characters or less for point ID resolution.

Length

Depending on the version of the PI API and the Historian Server, this Interface supports an

Extended Descriptor attribute whose length is at most 80 or 1023 characters. The

FactoryTalk Historian To Historian Interface User Guide 43

Historian Point Configuration

PI API

Historian Server

Maximum Length

1.6.0.2 or higher

2.x or higher

1023

1.6.0.2 or higher

Below 2.x

Below 1.6.0.2

2.x or higher

Below 1.6.0.2

Below 2.x

following table indicates the maximum length of this attribute for all the different combinations of PI API and Historian Server versions.

If the Historian Server version is earlier than 2.x or the PI API version is earlier than 1.6.0.2, and you want to use a maximum ExDesc length of 1023, you need to enable the PI SDK. See

Appendix B for information.

Unless the /tn or /ptid interface parameter is used, the extended descriptor may be used as an alternative source tag specification by using the keyword STAG=<tag name>. The

How PItoPI Finds Source Points section explains how the interface parameters affect which

receiving tag attributes are used for mapping to the source point and the order that the attributes are searched for a mapping.

Note that the STAG keyword must be the first four characters of the Exdesc attribute value. No spaces can precede the STAG keyword. The STAG keyword is case insensitive. If additional information is included after the STAG specification, the tag name must be terminated with a comma or enclosed in double quotation marks.

If the source tag name contains a comma within it, it must be enclosed in double quotation marks. For example, STAG="batchreactor1,temp" is a legitimate way to define a source tag name.

Performance Points

For UniInt-based interfaces, the extended descriptor is checked for the string

“PERFORMANCE_POINT”. If this character string is found, UniInt treats this point as a

performance point. See the section called Scan Class Performance Points.

UserInt1

Note: If the source tag name length exceeds 80 characters, users must use the

UserInt1 attribute for source point mapping. This is due to a limitation with the PI API programming library which supports tag names of 80 characters or less for point ID resolution.

Unless the /tn or /tnex interface parameter is used, the UserInt1 attribute can be used to specify the source tag point ID. The How PItoPI Finds Source Points section explains how the interface parameters affect which receiving tag attributes are used for mapping to the source point and the order that the attributes are searched for a mapping.

If the source tag name is longer than 80 characters then you must use this attribute to specify the source tag point ID. This is an alternative to using the source tag name. The advantage of using a point ID is that a tag name can change but the point ID cannot. For example, if the source tag name is used and that name is changed, the interface point will no longer be able to find it and will therefore not be able to collect its data. Using the source tag point ID will prevent a tag rename from stopping data updates.

Scan

By default, the Scan attribute has a value of 1, which means that scanning is turned on for the point. Setting the Scan attribute to 0 turns scanning off. If the Scan attribute is 0 when the interface starts, a message is written to the pipc.log and the tag is not loaded by the interface. There is one exception to the previous statement.

If any Historian point is removed from the interface while the interface is running (including setting the Scan attribute to 0), SCAN OFF will be written to the Historian point regardless of the value of the Scan attribute. Two examples of actions that would remove a Historian point from an interface are to change the point source or set the Scan attribute to 0. If an interface specific attribute is changed that causes the tag to be rejected by the interface, SCAN OFF will be written to the Historian point.

Shutdown

It is recommended that shutdown events are disabled for all interface tags. There are two shutdown events; when the Historian Server is stopped and when the interface is stopped. The Shutdown tag attribute is used to enable Historian Server shutdown events. See section

Interface Status Events for information regarding interface shutdown events.

Shutdown events are written to tags when the Historian Server is stopped to indicate data is not being collected. In some cases when the Historian Server is not running it creates a gap in data. However if interface history recovery is enabled a shutdown does not indicate a period of lost data.

If a tag is configured for shutdown events one is written when the server is stopped then again when it is started. Since the shutdown event on startup will be the current value for the interface tag it is used as the starting for history recovery. This results in a data gap for the Historian Server shutdown period.

Bufserv and PIBufss

It is undesirable to write shutdown events when buffering is being used. Bufserv and PIBufss are utility programs that provide the capability to store and forward events to a Historian Server, allowing continuous data collection when the Server is down for maintenance, upgrades, backups, and unexpected failures. That is, when Historian is shutdown, Bufserv or PIBufss will continue to collect data for the interface, making it undesirable to write

SHUTDOWN events to the Historian Points for this Interface. Disabling Shutdown is

recommended when sending data to a Highly Available Historian Server Collective. Refer to the Bufserv or PIBufss manuals for additional information.

Exception and Compression

Interface data may or may not be subjected to exception and compression depending on receiving Historian Server version and interface configuration. In either case it is recommended users configure the interface and tag attributes to prevent compression from causing data mismatches between Historian Servers.

FactoryTalk Historian To Historian Interface User Guide 45

Historian Point Configuration

Tag Attribute

Value

ExcDev/ExcDevPercent

CompDev/CompDevPercent

Source Tag Value

ExcMin & CompMin

ExcMax & CompMax

32767

Interface Configurations

Data collected by the interface has already passed exception on the source Historian Server. For this reason interface exception filtering should be disabled. This can be done by specifying the /sn switch in the startup configuration file. This tells the interface to bypass exception and send data directly to the snapshot table on the receiving Historian Server.

By default the interface will send history recovery and archive update data directly to the receiving Historian Server archive. The data write mode is configurable through the

Location5 tag attribute. If the /dc switch is specified in the interface startup file, data will

pass through compression on the receiving Historian Server regardless of server version. If the receiving Historian Server is Historian 3.2 or Historian 2 data is always subjected to compression whether or not the /dc switch is used.

Note: if a tag configured for archive data updates has its Location3 attribute set so it receives snapshot updates, data compression must be enabled to eliminate data mismatches between Historian Servers.

Recommended Tag Configurations

Each tag has attributes that are used to define exception and compression data filtering. These attributes specify a significant data change and the minimum and maximum time between events.

The following tag configurations are recommended to prevent data mismatches:

The ExcDev/ExcDevPercent and CompDev/CompDevPercent attributes define a significant data change. A new update must pass this value to pass data filtering.

The ExcMax and CompMax tag attributes set the maximum number of seconds between updates. When the value of this attribute is exceeded, the next update passes filtering regardless of whether or not it is a significant change in value. Tags should be configured with the maximum allowed values.

The ExcMin and CompMin tag attributes set the minimum number of seconds between updates. If a new value is received and the time difference between the new value and the current value does not exceed this value the update is filtered. Tags should be configured with a value of zero to prevent data from being filtered because of the time between updates.

By default, the largest ExcMax and CompMax values the interface supports is 32,767 seconds (~9hours). If the receiving Historian Server was a new installation of PI 3.3 or later, it is possible to have ExcMax and CompMax values of 4,294,967,295 seconds. In addition to the server version, the PI SDK must be enabled in the interface startup file by specifying

/pisdk=1.

DataAccess, PtAccess

Historian 3 nodes use these attributes to control client read/write access to the data and point attributes. Access may be specified for owner, group and world. The user and groups used must be created before assignment. Example: dataaccess=o:rw g:rw w:r,

ptaccess=o:rw g:r w:r.

Zero, Span

These attributes should match for the source and receiving points.

FactoryTalk Historian To Historian Interface User Guide 47

Digital State

String

STARTUP

HISTORYRECOVERY

SCANNING

SHUTDOWN

ACCESSDENIED

SRCDISCONNECT

RCVDISCONNECT

Digital State

String

RECONNECTING

PRIMARY

FAILOVER

SECONDARY

Attribute

Value

PointSource

PointType

Digital

Compressing

ExcDev

DigitalStateSet

As defined in the receiving PI3 server digital state database.

Chapter 7. Interface Status Tag Configuration

The following procedure describes how to create and configure interface status tags. These tags are created on the receiving Historian Server. See section Interface Status Tags for a complete description of this functionality.

1. Create a digital state set for the status tag. The following tables display the digital

state set definitions. Internal Status Tag:

Failover Status Tag:

2. Create a digital tag on the receiving Historian Server with the following attributes:

FactoryTalk Historian To Historian Interface User Guide 49

Chapter 8. Startup Command File

Command-line parameters can begin with a / or with a -. For example, the /ps=M and

-ps=M command-line parameters are equivalent.

Command file names have a .bat extension. The Windows continuation character (^) allows for the use of multiple lines for the startup command. The maximum length of each line is 1024 characters (1 kilobyte). The number of parameters is unlimited, and the maximum length of each parameter is 1024 characters.

The Historian Interface Configuration Utility (ICU) provides a tool for configuring the interface startup command file.

Configuring the interface with ICU

Note: ICU requires PI 2.0 and later.

The Historian Interface Configuration Utility provides a graphical user interface for configuring Historian Interfaces. If the interface is configured by the ICU, the batch file of the interface (PItoPI.bat) will be maintained by the ICU and all configuration changes will be kept in that file and the module database. The procedure below describes the necessary steps for using ICU to configure the FactoryTalk Historian to Historian Interface.

From the ICU menu, select Interface, then New Windows Interface Instance from EXE..., and then Browse to the PItoPI.exe executable file. Then, enter values for Point Source and Interface ID#. A window such as the following results:

FactoryTalk Historian To Historian Interface User Guide 51

Startup Command File

Interface name as displayed in the ICU (optional) will have Historian- pre-pended to this name and it will be the display name in the services menu.

Click Add. The following display should appear:

Note that in this example the Host FactoryTalk Historian System is mkellyD630. To configure the interface to communicate with a remote Historian Server, select „Interface => Connections…‟ item from ICU menu and select the default server. If the remote node is not present in the list of servers, it can be added.

Once the interface is added to ICU, near the top of the main ICU screen, the interface Type should be PItoPI. If not, use the drop-down box to change the interface Type to be PItoPI

Click on Apply to enable the ICU to manage this copy of the FactoryTalk Historian to Historian Interface.

The next step is to make selections in the interface-specific page (that is, PItoPI) that allow the user to enter values for the startup parameters that are particular to the FactoryTalk Historian to Historian Interface.

The PItoPI ICU control has 7 tabs for each scan class, plus the All Scan Classes settings. A yellow text box indicates that an invalid value has been entered, or that a required value has not been entered.

The next figure shows the All Scan Classes settings.

Notice the box for the Source host. This parameter is required and must be replaced with your server name, where the Historian to Historian data will be retrieved from.

The Settings for drop down list will always have one entry titled “All Scan Classes”, and will have one entry for each scan class defined for this interface. The settings defined on the “All

Scan Classes” tab are the settings that are used by the interface if one or more settings for any

of the scan classes is not provided. Since the FactoryTalk Historian to Historian Interface is a UniInt-based interface, in some

cases the user will need to make appropriate selections in the UniInt pages. These pages allows the user to access UniInt features through the ICU and to make changes to the behavior of the interface.

To set up the interface as a Windows Service, use the Service page. This page allows configuration of the interface to run as a service as well as to starting and stopping of the interface. The interface can also be run interactively from the ICU. To do that, open the Interface menu and then click Start Interactive.

For more detailed information on how to use the above-mentioned and other ICU pages and selections, please refer to the Historian Interface Configuration Utility User Manual. The next section describes the selections that are available from the PItoPI page. Once selections have been made on the ICU GUI, press the Apply button in order for ICU to make these changes to the interface‟s startup file.

FactoryTalk Historian To Historian Interface User Guide 53

Startup Command File

FactoryTalk Historian to Historian Interface page

Since the startup file of the FactoryTalk Historian to Historian Interface is maintained automatically by the ICU, use the PItoPI page to configure the startup parameters and do not make changes in the file manually. The following is the description of interface configuration parameters used in the ICU Control and corresponding manual parameters.

Required/General Tab

When All Scan Classes is selected in the Settings for list, the first tab will be titled Required. This is because the information provided in this first tab is required only for the All Scan Classes, and not for each scan class.

Required Parameters - Source host

The Source host is the name of the source Historian Server from which this FactoryTalk Historian to Historian interface is to get its data. (/SRC_HOST=hostname).

Required Parameters - PIx Server

The type of server needs to be selected in the combo box next to the Source host text box. The options are PI3 Server or PI2 Server.

Required Parameters - Event counter

The Event counter can only be configured for a particular scan class, so the Event counter box will remain disabled unless a scan class is selected in the Settings for combo box. (/EC=x).

PI2 Security File – Use PI2 security file

The PI2 Security File section is used only if the source host is a PI2 server. If a security file is to be used, select the Use PI2 security file check box.

PI2 Security File - Unique Part

The Unique part is the name suffix of tag security file on a Historian 2 system. The full name on the Historian 2 system is PItoPI<name>.SEC, where <name> is the portion specified in the Unique part box. (/SF=uniquename).

PI2 Security File - User

The User is the login user name of a PI user on Historian 2 node that the interface is to use. This is used for Historian 2 source systems. (/LN=username).

PI2 security File - Password

The Password is the login password of the PI user specified in the User box on Historian 2 node. This is used for Historian 2 source systems. (/PW=password).

Additional Parameters

This section is provided for any additional parameters that the current ICU Control does not support.

FactoryTalk Historian To Historian Interface User Guide 55

Startup Command File

History Recovery Tab

Maximum hours of history to recover

Number of hours to recover history for all points. Setting the value to 0 disables history recovery for all points. See section History Recovery for more information about history recovery. (/RH=hours)

The Use Default button is used to reset the value to the default setting of 8 maximum hours of history to recover.

Hours of history to recover per cycle

This is the number of hours of history to recover in each cycle through the point list. If the number of hours specified in the Hours of history to recover per cycle box is greater than or equal to the hours of history recovery requested in the Maximum hours of history to recover box, history will be recovered in one archive call from *- Hours of history to recover per

cycle hours to *. If Maximum hours of history to recover is greater than Hours of history to recover per cycle, the archive calls to retrieve history will be divided into N calls, where N = Maximum hours of history to recover / Hours of history to recover per cycle + 1. The calls, which start from (*-Maximum hours of history to recover), will each span Hours of history to recover per cycle hours. Each history increment is collected for all tags in the given scan

class before the next time increment is begun. If this field is set to zero, the default 24 hours will be used. (/RH_INC=hours)

The Use Default button is used to reset the value to the default setting of 24 hours for the number of Hours of history to recover per cycle.

Millisecond pause between history calls

The number of milliseconds to pause between history recovery calls. (/HRPAUSE=millisecond)

The Use Default button is used to reset the value to the default setting of 0 milliseconds to pause between history recovery calls.

Use history recovery only (no snapshot data collection)

If this check box is selected, tags do not sign up for exceptions. Each scheduled scan time (each scan class), history recovery is done from the last snapshot value to the current time. This box must be checked if you want to enter a History time range. (/HRONLY)

History time range (dd-mmm-yy:hh:mm:ss,dd-mmm-yy:hh:mm:ss)

Alternately, specifies a range of history to recover before exiting. The times must be specified using Historian Time string formats with a colon separating the date and the time. For example:

10-dec-98:10:00:00,10-dec-98:12:00:00

Note that these times are local to where the interface runs. This will recover two hours of data from the source to receiving system; put it into the

receiving FactoryTalk Historian System snapshot for all points and then exit. This switch will override the normal checking for the most recent snapshot time in the receiving database, thus out of order data may result. When time-range history recovery is enabled, the value specified by the /RH parameter is overridden. (/HRONLY=dd-mmm-yy:hh:mm:ss,dd-mmm-

yy:hh:mm:ss)

Start history recovery beginning with the first value prior to the start time.

This will retrieve history for all the points starting from the value immediately prior to the start time. The default is to begin with the first value after the start time. This can only be checked if the Use history recovery only check box has been checked.

FactoryTalk Historian To Historian Interface User Guide 57

Startup Command File

Debug Tab

Debug Parameters

The Debug Levels parameter is used to set a debug level for debug messaging per scan class. Check all types of debug messages that you would like to see logged. Any combination of debug levels can be applied. (/DB=#,#,#,#...)

Interface Status Tag on Receiving Historian Server:

This is the name of an interface status tag configured on receiving server. Click the Browse button to browse the point database for this interface status tag using the Tag Search utility. (/IST=tagname)

Location Tab

Use the Override Tag Location Code Settings check boxes to configure the interface to ignore individual tag location codes and to apply specific settings for each of the location codes.

Override Location 1

Ignore Location1 for each tag and load all tags configured for the specified point source regardless of Location1 and interface ID values. (/C1)

Override Location 2

Ignore Location2 for each tag and set Location2 value to be this number for all interface tags. (/C2=x)

Override Location 3

Ignore Location3 for each tag and set Location3 value to be this number for all interface tags. (/C3=x)

Override Location 4

Ignore Location4 for each tag. The value used here should be 1, to have all points for the interface sign up for exceptions, or 2, to have all points retrieve history only. (/C4=x)

Override Location 5

Ignore Location5 for each tag and set all points for the interface to the same value of this parameter (i.e., 0, 1, 2, or 3). (/C5=x)

FactoryTalk Historian To Historian Interface User Guide 59

Startup Command File

Optional Tab

Apply tag’s compression specifications to data retrieved during history recovery.

Use compression specifications in tag configurations to send data retrieved during history recovery with compression. Usually data is retrieved from source server and sent to receiving server without compression during history recovery. (/DC)

Source tag definition attribute.

Use TagName on both (Ignoring ExDesc and InstrumentTag point attributes). Do not check the InstrumentTag, ExDesc, or UserInt1 attributes for source tag definitions. Use

TagName to identify the point on both source and receiving Historian Servers. (/TN)

Use ExDesc or TagName (Ignoring InstrumentTag point attribute). The source tag definition will be found in the ExDesc or TagName attribute. Ignore the InstrumentTag and

UserInt1 attributes. This parameter is useful for PI2 to PI3 migrations. (/TNEX)

Use UserInt1 (Ignoring ExDesc and InstrumentTag point attributes). The source tag definition will be found in the UserInt1 attribute. Ignore the ExDesc, InstrumentTag, and Tag point attributes. (/PTID)

The How PItoPI Finds Source Points section explains how the interface parameters affect which receiving tag attributes are used for mapping to the source point and the order that the attributes are searched for a mapping.

Specify maximum events to retrieve for a single point in each call to get history.

This parameter is available for PI 2.0 and later receiving servers. It sets the maximum number of events to retrieve for a single point in each call to get history. With each call to retrieve history, one call is made to put it into the receiving server. At least one of these calls will be over the network, so using a small number could result in performance problems. (/MH=x,

default: 1000)

Specify maximum number of exception events retrieved per data request.

This parameter sets the maximum number of exceptions events retrieved per data request. A large count reduces the number of calls required for acquiring exception updates. A small count reduces the time to complete each request (for troubleshooting network timeout issues). (/ME=#, default: 5000)

Set time interval between clearing exception queue during history recovery.

This parameter sets the time interval between clearing the exception queue on the source Historian Server for exception data scan classes. By default the interface will collect exceptions from the source Historian Server every 5 seconds during history recovery to prevent overflowing the queue. Users may want to adjust this time interval to tune history recovery performance. (/RH_QCKECK=#, default: 5)

Specify the frequency that the interface calculates time offset between Historian Servers.

This parameter sets the frequency in seconds at which the interface will calculate time offsets between Historian Servers. By default the interface will calculate time offsets every 30 seconds. (/OC=#, default: 30)

FactoryTalk Historian To Historian Interface User Guide 61

Startup Command File

Opt Cont Tab

Source Host reconnection delay.

This parameter sets the time delay for attempting to reconnect to source Historian Server after a disruption. The number is entered in seconds and converted to milliseconds before being saved in the batch file. This number must be between 1 second and 8 hours. (/DELAYS=x,

default: 0 seconds)

Receiving Host reconnection delay.

This parameter set the time delay for attempting to reconnect to receiving Historian Server after a disruption. The number is entered in seconds and converted to milliseconds before being saved in the batch file. This number must be between 1 second and 8 hours. (/DELAYR= x, default: 0 seconds)

Suppress writing I/O Timeout to tags upon reestablishment of a lost connection to the source Historian Server

When setting Location3 to write “I/O Timeout” for any tags, use this parameter to suppress the I/O Timeout state written to these tags upon reestablishment of a lost connection to the source Historian Server. If this parameter is not set, the state written at reconnection will prevent history from being recovered for the period of the disconnection. (/TS)

Source Historian Server Failover Tab

Enable PItoPI Failover

This check box is used to allow the configuration of the failover. Until this box is checked none of the items on this tab are enabled. Note that having this check makes items 2 and 3 required since they are in yellow.

Source Server Interface Status Utility Tag

This is the name of a Historian Interface Status Utility tag configured on the source server defined in /SRC_HOST=hostname. Click the Browse button to invoke the Tag Search utility to browse for this tag. (/SSU1=tagname)

Secondary Source Server Node Name

This is the name of the second source node from which to retrieve data. This must be a Historian 3.x Historian Server node because the port number of 5450 will be appended to the end of this name when it is saved in the batch file. (/SEC_SRC=nodename:5450)

Secondary Source Int Status Utility Tag

This the name of a Historian Interface Status Utility tag configured on the source server defined in /SEC_SRC=hostname. Click the Browse button to invoke the Tag Search utility to browse for this tag. (/SSU2=tagname)

FactoryTalk Historian To Historian Interface User Guide 63

Startup Command File

Number of connection attempts to source server

This parameter is used to specify the number of times to try connecting to source server if connection fails the first time. It can be used to restrict failover from occurring until after a certain number of attempts made to connect to the primary server have failed. The default number of attempts is 1.(/NT=x)

Enable failover status logging.

This check box is used to enable failover status logging. By checking this box, the user is allowed to enter a Receiving Server Status Tag. This tagname entered in this text box is the failover status tag configured on receiving server. Click the Browse button to invoke the Tag Search utility to browse for this tag. (/FST=tagname)

Note: The UniInt Interface User Manual includes details about other command-line parameters, which may be useful.

Configuring Interface Startup Files

The interface has two startup configuration files; PItoPI.bat and PItoPI.ini. The .bat file is required and is the primary file for specifying interface configurations. The .ini file should only be used if configuring one copy of the interface to collect data from multiple source Historian Servers. In this configuration each scan class can be configured for a unique source Historian Server. This is not recommended for exception data collection. Interface performance is maximized by running a separate copy of the interface for each source Historian Server.

When using the .ini file, global parameters such as point source are defined in the .bat file. Scan class specific parameters are defined in the .ini file, such as source Historian Server. When a parameter is set in both the .bat and .ini file, the .ini file takes precedence.

When configuring the .bat startup file the continuation character ^ can be used to allow multiple lines for defining parameters. The maximum length for a single line is 1024 characters (1 kilobyte). The number of parameters is unlimited, and the maximum length of each parameter is 1024 characters.

Command-line Parameters

These parameters are displayed in five groups: General Interface Operation, History Recovery and Archive Data Collection, Exception Data Collection, Tag Attribute Override, and Server-level Failover.

.BAT

.INI

Description

/db=#

Optional

DebugFlags

/db=1 : Max debug /db=2 : Startup processing /db=3 : Historian Server connections /db=4 : PI2 security validation /db=5 : Tag additions, edits, deletions /db=6 : Data read & writes /db=7 : Failover

Example: /db=2,4,5

/delayr=#

Optional Default:

/delayr=0

Millisecond time delay between reconnection attempts to the receiving Historian Server. Units are in milliseconds. Valid values are between 0 and 28800000ms (8 hours).

/delays=#

Optional Default:

/delays=0

Millisecond time delay between reconnection attempts to the source Historian Server. Valid values are between 0 and 28800000ms (8 hours).

/ec=#

Optional

EventCounter

The first instance of the /ec parameter on the command-line is used to specify a counter number, #, for an I/O Rate point. Range allowed is 1-34 and 51-200. If the # is not specified, then the default event counter is 1. Also, if the /ec parameter is not specified at all, there is still a default event

counter of 1 associated with the interface. If there is an I/O Rate point that is associated with an event counter of 1, each copy of the interface that is running without

/ec=#explicitly defined will write to the same

I/O Rate point. This means either explicitly defining an event counter other than 1 for each copy of the interface or not associating any I/O Rate points with event counter 1. Configuration of I/O Rate points is discussed in the section called I/O Rate Point.

/f=SS.##

/f=SS.##,SS.##

/f=HH:MM:SS.##

/f=HH:MM:SS.##, hh:mm:ss.##

Required

The /f parameter defines the time period between scans in terms of hours (HH), minutes (MM), seconds (SS) and sub-seconds (##). The scans can be scheduled to occur at discrete moments in time with an optional

time offset specified in terms of hours (hh), minutes (mm), seconds (ss) and subseconds (##). If HH and MM are omitted, then the time period that is specified is assumed to

be in seconds. Each instance of the /f parameter on the

command-line defines a scan class for the interface. There is no limit to the number of scan classes that can be defined. The first occurrence of the /f parameter on the

command-line defines the first scan class of

General Interface Operation

FactoryTalk Historian To Historian Interface User Guide 65

Startup Command File

.BAT

.INI

Description

the interface; the second occurrence defines the second scan class, and so on. Historian Points are associated with a particular scan class via the Location4 Historian Point attribute. For example, all Historian Points that have Location4 set to 1 will receive input values at the frequency defined by the first scan class. Similarly, all points that have Location4 set to 2 will receive input values at the frequency specified by the second scan class, and so on.

Two scan classes are defined in the following example:

/f=00:01:00,00:00:05 /f=00:00:07

or, equivalently:

/f=60,5 /f=7

The first scan class has a scanning frequency of 1 minute with an offset of 5 seconds, and the second scan class has a scanning frequency of 7 seconds. When an offset is specified, the scans occur at discrete moments in time according to the formula:

scan times = (reference time) + n(frequency) + offset

where n is an integer and the reference time is midnight on the day that the interface was started. In the above example, frequency is 60 seconds and offset is 5 seconds for the first scan class. This means that if the interface was started at 05:06:06, the first scan would be at 05:07:05, the second scan would be at 05:08:05, and so on. Since no offset is specified for the second scan class, the absolute scan times are undefined.

The definition of a scan class does not guarantee that the associated points will be scanned at the given frequency. If the interface is under a large load, then some scans may occur late or be skipped entirely.

See the section “Performance Summaries” in

the UniInt Interface User Manual.doc for more information on skipped or missed scans.

Sub-second Scan Classes

Sub-second scan classes can be defined on the command-line, such as

/f=0.5 /f=00:00:00.1

where the scanning frequency associated with the first scan class is 0.5 seconds and the scanning frequency associated with the second scan class is 0.1 of a second.

Similarly, sub-second scan classes with subsecond offsets can be defined, such as

/f=0.5,0.2 /f=1,0 Wall Clock Scheduling

Scan classes that strictly adhere to wall clock scheduling are now possible. This feature is available for interfaces that run on Windows.

.BAT

.INI

Description

Previously, wall clock scheduling was possible, but not across daylight saving time. For example,

/f=24:00:00,08:00:00 corresponds to

1 scan a day starting at 8 AM. However, after a Daylight Saving Time change, the scan would occur either at 7 AM or 9 AM, depending upon the direction of the time shift. To schedule a scan once a day at 8 AM (even across daylight saving time), use

/f=24:00:00,00:08:00,L. The ,L at

the end of the scan class tells UniInt to use the new wall clock scheduling algorithm.

/host=name:port

Required

Name or IP address of receiving Historian Server.

Name is the IP address of the Historian Sever

node or the domain name of the Historian Server node. Port is the port number for

TCP/IP communication. The port number is 545 (Historian 2) or 5450 (PI3). It is recommended to explicitly define the host and port on the command-line with the

/host parameter. Nevertheless, if either the

host or port is not specified, the interface will attempt to use defaults.

Examples: The interface is running on an interface node,

the domain name of the Historian home node is Marvin, and the IP address of Marvin is

206.79.198.30. Valid /host parameters

would be:

/host=marvin /host=marvin:5450

/host=206.79.198.30

/host=206.79.198.30:5450

/id=x

Required

The /id parameter is used to specify the interface identifier.

The interface identifier is a string that is no longer than 9 characters in length. UniInt concatenates this string to the header that is used to identify error messages as belonging to a particular interface. See the Appendix A:

Error and Informational Messages for more

information. UniInt always uses the /id parameter in the fashion described above. This interface also

uses the /id parameter to identify a particular interface copy number that

corresponds to an integer value that is assigned to one of the Location code point attributes, most frequently Location1. For this interface, use only numeric characters in the identifier. For example,

/id=1

FactoryTalk Historian To Historian Interface User Guide 67

Startup Command File

.BAT

.INI

Description

/ist=tagname

Optional

Name of interface status tag.

/ist=<tagname>

where < tagname> is a digital tag on the receiving Historian Server.

/ln=username

Optional

SourceLogin

/oc=#

Optional Default:

/oc=30

Number of seconds between calculating time offset between the interface and Historian Server nodes.

/ps=x

Required

The /ps parameter specifies the point source for the interface. X is not case sensitive and can be any single or multiple

character string. For example, /ps=P and

/ps=p are equivalent.

The point source that is assigned with the

/ps parameter corresponds to the

PointSource attribute of individual Historian Points. The interface will attempt to load only those Historian Points with the appropriate point source.

/pw=password

Optional

SourcePassword

/sf=filename

Required for Historian 2 source

SecurityFile

Used for locating the security file on a PI2 source server.

This switch specifies the <name> part of the file name. Note that the complete file name must have this format:

PItoPI<name>.SEC

where <name> is the portion specified by

/sf

/src_host=name: port

Required

SourceHost

Name or IP address of source Historian Server.

/src_host=node_name:tcpip_port

The port number is 545 (Historian 2) or 5450 (Historian 3).

.BAT

.INI

Description

/stopstat

/stopatat=

digstate

Default:

/stopstat=

"Intf shut"

Optional

If the /stopstat parameter is present on the startup command line, then the

digital state Intf Shut will be written to each Historian Point when the interface is

stopped. If /stopstat=digstate is present on

the command line, then the digital state,

digstate, will be written to each Historian

Point when the interface is stopped. UniInt uses the first occurrence in the table.

If neither /stopstat nor

/stopstat=digstate is specified on the

command line, then no digital states will be written when the interface is shut down.

Note: The /stopstat parameter is disabled If the interface is running in a UniInt

failover configuration as defined in the UniInt

Failover Configuration section of this manual.

Therefore, the digital state, digstate, will not be written to each Historian Point when

the interface is stopped. This prevents the digital state being written to Historian Points while a redundant system is also writing data to the same Historian Points. The

/stopstat parameter is disabled even if

there is only one interface active in the failover configuration.

Examples:

/stopstat=shutdown

/stopstat="Intf Shut"

The entire digstate value should be enclosed within double quotes when there is

a space in digstate.

/ts

Optional

Suppress „IO Timeout‟ events when

reconnecting to source Historian Server. These events are configured through

Location3 attribute.

If this switch is not set, the event written at reconnection will prevent history from being recovered for the period of the disconnection.

FactoryTalk Historian To Historian Interface User Guide 69

Startup Command File

.BAT

.INI

Description

/dc

Optional

Apply data compression to history recovery and archive scan updates. The default behavior is for this data to bypass compression.

This switch must be specified to prevent data mismatches if tags are configured to include snapshot value with archive scan updates.

/hronly= start,end

Optional

HistOnly

Used without "=start,end" to disable exception data collection.

Also used to specify time range specific history recovery:

/hronly=starttime,endtime

The times must be specified using Historian Time string formats with a colon or underscore separating the date and the time:

/hronly=dd-mmm-yy:hh:mm:ss,ddmmm-yy:hh:mm:ss

/hronly=dd-mmm-yy_hh:mm:ss,ddmmm-yy_hh:mm:ss

For example:

/hronly=10-dec-98:10:00,10-dec-

98:12:00

/hronly=10-dec-98_10:00,10-dec98_12:00

Note: timestamps are local to where the interface runs. This is important if source/receiving Historian Server are in a

different timezone.

When configured for time range specific history recovery the interface recovers data then exits.

/hrpause=#

Optional Default:

/hrpause=0

HistPause

Milliseconds to pause between tags during history recovery. Used to throttle archive data retrieval during history recovery.

/mh=x

Optional Default:

/mh=1000

Available for PI 3.3 or later receiving Historian Servers.

Sets the maximum number of archive events retrieved per data request. During history recovery and archive data collection, the interface specifies the maximum number of events to return. If more than the maximum exist, the interface makes multiple calls until all events are retrieved for the time period.

Increasing the default may increase data throughput for archive data retrieval.

History Recovery and Archive Data Collection

.BAT

.INI

Description

/ns

Optional

Boundary condition for data retrieval with a timerange specific history recovery.

When specified the interface will start history recovery beginning with the first value prior to the start time. The default behavior is to begin with the first value after the start time.

/rh=#

Optional Default:

/rh=8

HistRecovery

Hours of history recovery to perform. There is no limit on the number of hours for

history recovery. However special preparations may be necessary if the recovery period spans beyond the primary archive. For example there may not be enough space in the target (nonprimary) archive for the recovery data, or nonprimary archives may not have space allocated for newly created tags. See the Historian Server System Management Guide for information on backfilling data.

/rh_inc=#

Optional Default:

/rh_inc=24

MaxArcTimespan

Time increments within the total /rh recovery period.

For example, /rh=48 and /rh_inc=24. The interface will cycle through the tag list twice. On

the first cycle, data recovery is performed for the first 24-hour period. On the second cycle, the second 24-hour period is collected to complete the total 48 hour recovery period.

/rh_qcheck=#

Optional Default:

/rh_qcheck=5

For exception data scan classes, sets the time interval between clearing the exception queue on the source Historian Server during history recovery.

By default the interface will collect exceptions from the source Historian Server every 5 seconds during history recovery to prevent overflowing the queue. Users may want to adjust this time interval to tune history recovery performance.

.BAT

.INI

Description

/me=#

Optional Default:

/me=5000

Sets the maximum number of exception events retrieved per data request. A large count reduces the number of calls required for acquiring exception updates. A small count reduces the time to complete each request (for troubleshooting network timeout issues).

/sn

Optional

Bypass exception filtering for data collected from the source Historian Server. This data has already passed exception for the source tag so additional data filtering can only lead to data mismatches between Historian Servers.

Exception Data Collection

FactoryTalk Historian To Historian Interface User Guide 71

Startup Command File

.BAT

.INI

Description

/c1

Optional

Location1 tag attribute override.

Load all tags configured for the specified point source regardless of Location1and interface ID values.

/c2=#

Optional

Location2 tag attribute override.

Ignore Location2 for each tag and use the specified value. Valid values are 0-7.

/c3=#

Optional

Location3 tag attribute override.

Ignore Location3 for each tag and use the specified value. Valid values are 0-15.

/c4=#

Optional

Location4 tag attribute override.

Ignore Location4 for each tag and use the specified value. Valid values are 1 (exception data

collection) or 2 (archive data collection).

/c5=#

Optional

Location5 tag attribute override.

Ignore Location5 for each tag and use the specified value. Valid values are 0-3.

/ptid

Optional

Source tag point ID is specified in UserInt1 attribute. Ignore InstrumentTag, Exdesc and Tag name attributes.

Note: this switch is not compatible with source Historian Server failover since point IDs will not necessarily match between source Historian Servers. If the source Historian Servers are part of a Historian Collective use /tn instead.

/tn

Optional

Source tag name is same as interface tag name. Ignore InstrumentTag, Exdesc and

UserInt1 attributes.

/tnex

Optional

Source tag name is located in the Exdesc or Tag name attribute and the InstrumentTag and

UserInt1 attributes are ignored for identifying

source tag.

.BAT

.INI

Description

/fst=tag

Optional

Name of failover status tag.

/fst=<tagname>

where <tagname> is a digital tag on the receiving Historian Server.

/nt=#

Optional Default:

/nt=1

Number of reconnection attempts to source Historian Server before initiating a failover. Valid values are 0 and greater.

Prevents failover flip-flop when experiencing intermittent network updates.

Tag Attribute Override

Server-Level Failover

.BAT

.INI

Description

/sec_src= node :port

Required

Name or IP address of the secondary source Historian Server.

/sec_src=node_name:tcpip_port

The port number is 5450 (PI3). PI2 is not supported for source Historian Server failover.

/ssu1=tag

Required

Historian Interface Status Utility tag name for the

/src_host source Historian Server.

/ssu1=<tagname>

Required for monitoring source data quality (current or stale data).

/ssu2=tag

Required

Historian Interface Status Utility tag name for the

/sec_src source Historian Server.

/ssu2=<tagname>

Required for monitoring source data quality (current or stale data).

Sample Startup Configuration Files

The startup files for the interface reside in the directory PIHOME\Interfaces\PItoPI where PIHOME is defined in %WINDIR%\pipc.ini by the installation program. Typically,

PIHOME is c:\pipc. The startup files consist of PItoPI.bat and PItoPI.ini.

Sample PItoPI.bat File

REM=============================================================== REM

REM PItoPI.bat REM REM Sample startup file for the PItoPI TCP/IP Interface REM REM=============================================================== REM REM Rockwell Automation strongly recommends using ICU to modify startup files. REM REM Sample command line REM .\PItoPI.exe ^ /host=XXXXXX:5450 ^ /src_host=XXXXXX:5450 ^ /ps=PItoPI ^ /id=1 ^ /f=10

REM End of PItoPI.bat File

FactoryTalk Historian To Historian Interface User Guide 73

Startup Command File

Sample PItoPI.ini File

; Sample PItoPI.ini ; ;-----------------------------------------------------------------; Purpose: ; This file should be used in conjunction with PItoPI.bat. It is only ; required when a user wishes to collect data from multiple source ; servers with a single copy of the interface. ; ; the headings read [FT-PItoPI-x.y] where; ; x = interface id ; y = scan class (if specified) ;-----------------------------------------------------------------; [FT-PItoPI-1] ;EventCounter=1 ;MaxArcTimespan=24 ; [FT-PItoPI-1.1] ;SourceHost=XXXXXX:5450 ;HistRecovery=48 ; [FT-PItoPI-1.2] ;SourceHost=XXXXXX:5450 ;HistRecovery=72 ; ;------------------------------------------------------------------; List of possible parameters ; ;SourceHost=XXXXXX:5450 Name of source Historian Server, ; port=5450 for PI3 and 545 for PI2. This ; field MUST BE an IP address. ;ReceivingHost=XXXXXX:5450 Name of the receiving Historian Server, ; port=5450 for PI3 and 545 for PI2. This ; field MUST BE an IP address. ;SecurityFile=securityfile Required if PI2, <name> part of security file ; PItoPI<name>.SEC ;SourceLogin=userid PI2 PI user name ;SourcePassword=password PI2 PI user password ;EventCounter=# Number of event counter defined in ; \dat\iorates.dat file ;HistRecovery=# total hours of history recovery, default=8hrs ;MaxArcTimespan=# history recovery increment, divided into total ; hours of history recovery (HistRecovery), ; default=24hrs ;HistPause=# pause between history recovery increments in ; milliseconds ;HistOnly=# flag to disable exception data collection ; (0=off, 1=on) ;DebugFlags=#,#,#,#... Generates additional messages for troubleshooting ; comma separated list: 1,2,3,4,5,6,7 ;-------------------------------------------------------------------

; end of sample PItoPI.ini

Chapter 9. UniInt Failover Configuration

Introduction

To minimize data loss during a single point of failure within a system, UniInt provides two failover schemas: (1) synchronization through the data source and (2) synchronization through a shared file. Synchronization through the data source is Phase 1, and synchronization through a shared file is Phase 2.

Phase 1 UniInt Failover uses the data source itself to synchronize failover operations and provides a hot failover, no data loss solution when a single point of failure occurs. For this option, the data source must be able to communicate with and provide data for two interfaces simultaneously. Additionally, the failover configuration requires the interface to support outputs.

Phase 2 UniInt Failover uses a shared file to synchronize failover operations and provides for hot, warm, or cold failover. The Phase 2 hot failover configuration provides a no data loss solution for a single point of failure similar to Phase 1. However, in warm and cold failover configurations, you can expect a small period of data loss during a single point of failure transition.

Note: This interface supports only Phase 2 failover.

You can also configure the UniInt interface level failover to send data to a High Availability (HA) Historian Server collective. The collective provides redundant Historian Servers to allow for the uninterrupted collection and presentation of Historian Time series data. In an HA configuration, Historian Servers can be taken down for maintenance or repair. The HA Historian Server collective is described in the Historian Server Reference Guide.

When configured for UniInt failover, the interface routes all FactoryTalk Historian data through a state machine. The state machine determines whether to queue data or send it directly to Historian depending on the current state of the interface. When the interface is in the active state, data sent through the interface gets routed directly to Historian. In the backup state, data from the interface gets queued for a short period. Queued data in the backup interface ensures a no-data loss failover under normal circumstances for Phase 1 and for the hot failover configuration of Phase 2. The same algorithm of queuing events while in backup is used for output data.

FactoryTalk Historian To Historian Interface User Guide 75

UniInt Failover Configuration

Quick Overview

The Quick Overview below may be used to configure this Interface for failover. The failover configuration requires the two copies of the interface participating in failover be installed on different nodes. Users should verify non-failover interface operation as discussed in the

Installation Checklist section of this manual prior to configuring the interface for failover

operations. If you are not familiar with UniInt failover configuration, return to this section after reading the rest of the UniInt Failover Configuration section in detail. If a failure occurs at any step below, correct the error and start again at the beginning of step 6 Test in the table below. For the discussion below, the first copy of the interface configured and tested will be considered the primary interface and the second copy of the interface configured will be the backup interface.

Configuration

 One Data Source  Two Interfaces

Prerequisites

 Interface 1 is the Primary interface for collection of FactoryTalk Historian data from

the data source.

 Interface 2 is the Backup interface for collection of FactoryTalk Historian data from

the data source.

 You must set up a shared file.  Phase 2: The shared file must store data for five failover tags: (1) Active ID,

(2) Heartbeat 1, (3) Heartbeat 2, (4) Device Status 1 and (5) Device Status 2.

 Each interface must be configured with two required failover command line

parameters: (1) its FailoverID number (/UFO_ID); (2) the FailoverID number of its Backup interface (/UFO_OtherID). You must also specify the name of the Historian Server host for exceptions and Historian tag updates.

 All other configuration parameters for the two interfaces must be identical.

Business Network

Process Network

IF-Node1

PI-Interface.exe /host=PrimaryPI /UFO_ID=1 /UFO_OTHERID=2 /UFO_TYPE=HOT /UFO_SYNC=\\FileSvr\UFO\Intf_PS_1.dat

IF-Node2

PI-Interface.exe /host=SecondaryPI /UFO_ID=2 /UFO_OTHERID=1 /UFO_TYPE=HOT /UFO_SYNC=\\FileSvr\UFO\Intf_PS_1.dat

DataSource

DCS/PLC/Data Server

Client

Process Book DataLink

PrimaryPI

PI Server Role = 1

SecondaryPI

PI Server Role = 2

Data register 0

. . .

Data register n

FileSvr

.\UFO\Intf_PS_1.dat

Synchronization through a Shared File (Phase 2)

Figure 4: Synchronization through a Shared File (Phase 2) Failover Architecture

The Phase 2 failover architecture is shown in Figure 4 which depicts a typical network setup including the path to the synchronization file located on a File Server (FileSvr). Other configurations may be supported and this figure is used only as an example for the following discussion.

For a more detailed explanation of this synchronization method, see Detailed Explanation of

Synchronization through a Shared File (Phase 2)

FactoryTalk Historian To Historian Interface User Guide 77

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Step

Description

Verify non-failover interface operation as described in the Installation Checklist section of this manual

Configure the Shared File

Choose a location for the shared file. The file can reside on one of the interface nodes but Rockwell Automation strongly recommends that you put the file on a dedicated file server that has no other role in data collection.

Setup a file share and make sure to assign the permissions so that both Primary and Backup interfaces have read/write access to the file.

Configure the interface parameters

Use the Failover section of the Interface Configuration Utility (ICU) to enable failover and create two parameters for each interface: (1) a Failover ID number for the interface; and (2) the Failover ID number for its backup interface.

The Failover ID for each interface must be unique and each interface must know the Failover ID of its backup interface.

If the interface can perform using either Phase 1 or Phase 2 pick the Phase 2 radio button in the ICU.

Select the synchronization File Path and File to use for Failover. Select the type of failover required (Cold, Warm, Hot). The choice depends on what types

of failover the interface supports.

Ensure that the user name assigned in the “Log on as:” parameter in the Service section

of the ICU is a user that has read/write access to the folder where the shared file will reside.

All other command line parameters for the primary and secondary interfaces must be identical.

If you use a Historian Collective, you must point the primary and secondary interfaces to different members of the collective by setting the SDK Member under the PI Host Information section of the ICU.

[Option] Set the update rate for the heartbeat point if you need a value other than the default of 5000 milliseconds.

Configure the Historian tags

Configure five Historian tags for the interface: the Active ID, Heartbeat 1, Heartbeat2, Device Status 1 and Device Status 2. You can also configure two state tags for monitoring the status of the interfaces.

Do not confuse the failover Device status tags with the UniInt Health Device Status tags. The information in the two tags is similar, but the failover device status tags are integer values and the health device status tags are string values.

Tag

ExDesc

digitalset

UniInt does not examine the remaining attributes, but the PointSource and Location1 must match

ActiveID

[UFO2_ACTIVEID]

IF1_Heartbeat

(IF-Node1)

[UFO2_HEARTBEAT:#]

IF2_Heartbeat

(IF-Node2)

[UFO2_HEARTBEAT:#]

IF1_DeviceStatus

(IF-Node1)

[UFO2_DEVICESTAT:#]

IF2_DeviceStatus

(IF-Node2)

[UFO2_DEVICESTAT:#]

IF1_State

(IF-Node1)

[UFO2_STATE:#]

IF_State

IF2_State

(IF-Node2)

[UFO2_STATE:#]

IF_State

Configuring Synchronization through a Shared File (Phase 2)

Step

Description

Test the configuration.

After configuring the shared file and the interface and Historian tags, the interface should be ready to run.

See Troubleshooting UniInt Failover for help resolving Failover issues.

1. Start the primary interface interactively without buffering.

2. Verify a successful interface start by reviewing the pipc.log file. The log file will contain messages that indicate the failover state of the interface. A successful start with only a single interface copy running will be indicated by

an informational message stating “UniInt failover: Interface in the “Primary” state and actively sending data to Historian. Backup interface not available.” If the interface has

failed to start, an error message will appear in the log file. For details relating to informational and error messages, refer to the Messages section below.

3. Verify data on the Historian Server using available Historian tools.

 The Active ID control tag on the Historian Server must be set to the

value of the running copy of the interface as defined by the /UFO_ID startup command-line parameter.

 The Heartbeat control tag on the Historian Server must be changing

values at a rate specified by the /UFO_Interval startup commandline parameter.

4. Stop the primary interface.

5. Start the backup interface interactively without buffering. Notice that this copy will become the primary because the other copy is stopped.

6. Repeat steps 2, 3, and 4.

7. Stop the backup interface.

8. Start buffering.

9. Start the primary interface interactively.

10. Once the primary interface has successfully started and is collecting data, start the backup interface interactively.

11. Verify that both copies of the interface are running in a failover configuration.

 Review the pipc.log file for the copy of the interface that was started

first. The log file will contain messages that indicate the failover state of the interface. The state of this interface must have changed as

indicated with an informational message stating “UniInt failover:

Interface in the “Primary” state and actively sending

data to Historian. Backup interface available.” If the

interface has not changed to this state, browse the log file for error messages. For details relating to informational and error messages, refer to the Messages section below.

 Review the pipc.log file for the copy of the interface that was started

last. The log file will contain messages that indicate the failover state of the interface. A successful start of the interface will be indicated by an

informational message stating “UniInt failover: Interface in the “Backup” state.” If the interface has failed to start, an error

message will appear in the log file. For details relating to informational and error messages, refer to the Messages section below.

12. Verify data on the Historian Server using available Historian tools.

 The Active ID control tag on the Historian Server must be set to the

value of the running copy of the interface that was started first as

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Step

Description

defined by the /UFO_ID startup command-line parameter.

 The Heartbeat control tags for both copies of the interface on the

Historian Server must be changing values at a rate specified by the /UFO_Interval startup command-line parameter or the scan class which the points have been built against.

13. Test Failover by stopping the primary interface.

14. Verify the backup interface has assumed the role of primary by searching the pipc.log file for a message indicating the backup interface has changed to

the “UniInt failover: Interface in the “Primary” state and

actively sending data to Historian. Backup interface not available.” The backup interface is now considered primary and the

previous primary interface is now backup.

15. Verify no loss of data in Historian. There may be an overlap of data due to the queuing of data. However, there must be no data loss.

16. Start the backup interface. Once the primary interface detects a backup interface, the primary interface will now change state indicating “UniInt

failover: Interface in the “Primary” state and actively

sending data to Historian. Backup interface available.” In

the pipc.log file.

17. Verify the backup interface starts and assumes the role of backup. A successful start of the backup interface will be indicated by an informational

message stating “UniInt failover: Interface in “Backup

state.” Since this is the initial state of the interface, the informational message will be near the beginning of the start sequence of the pipc.log file.

18. Test failover with different failure scenarios (e.g. loss of Historian connection for a single interface copy). UniInt failover guarantees no data loss with a single point of failure. Verify no data loss by checking the data in Historian and on the data source.

19. Stop both copies of the interface, start buffering, start each interface as a service.

20. Verify data as stated above.

21. To designate a specific interface as primary. Set the Active ID point on the Data Source Server of the desired primary interface as defined by the /UFO_ID startup command-line parameter.

Parameter

Required/ Optional

Description

Value/Default

/UFO_ID=#

Required

Failover ID for IF-Node1 This value must be different from

the failover ID of IF-Node2.

Any positive, nonzero integer / 1

Required

Failover ID for IF-Node2 This value must be different from

the failover ID of IF-Node1.

Any positive, nonzero integer / 2

/UFO_OtherID=#

Required

Other Failover ID for IF-Node1 The value must be equal to the

Failover ID configured for the interface on IF-Node2.

Same value as Failover ID for IF-Node2 / 2

Required

Other Failover ID for IF-Node2 The value must be equal to the

Failover ID configured for the interface on IF-Node1.

Same value as Failover ID for IF-Node1 / 1

/UFO_Sync= path/[filename]

Required for Phase 2 synchronization

The Failover File Synchronization Filepath and Optional Filename specify the path to the shared file used for failover synchronization and an optional filename used to specify a user defined filename in lieu of the default filename.

The path to the shared file directory can be a fully qualified machine name and directory, a mapped drive letter, or a local path if the shared file is on one of the interface nodes. The path must be terminated by a slash ( / ) or backslash ( \ ) character. If no terminating slash is found, in the

/UFO_Sync parameter, the

interface interprets the final character string as an optional filename.

The optional filename can be any valid filename. If the file does not

Any valid pathname / any valid filename

The default filename is generated as

executablename_ pointsource_ interfaceID.dat

Configuring UniInt Failover through a Shared File (Phase 2)

Start-Up Parameters

Note: The /stopstat parameter is disabled If the interface is running in a UniInt

failover configuration. Therefore, the digital state, digstate, will not be written to each Historian Point when the interface is stopped. This prevents the digital state being written to Historian Points while a redundant system is also writing data to the same Historian Points. The /stopstat parameter is disabled even if there is only one interface active in the failover configuration.

The following table lists the start-up parameters used by UniInt Failover Phase 2. All of the parameters are required except the /UFO_Interval startup parameter. See the table below for further explanation.

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Parameter

Required/ Optional

Description

Value/Default

exist, the first interface to start attempts to create the file.

Note: If using the optional filename, do not supply a terminating slash or backslash character.

If there are any spaces in the path or filename, the entire path and filename must be enclosed in quotes.

Note: If you use the backslash and path separators and enclose the path in double quotes, the final backslash must be a double backslash (\\). Otherwise the closing double quote becomes part of the parameter instead of a parameter separator.

Each node in the failover configuration must specify the same path and filename and must have read, write, and file creation rights to the shared directory specified by the path parameter.

The service that the interface runs against must specify a valid logon user account under the “Log On” tab for the service properties.

/UFO_Type=type

Required

The Failover Type indicates which type of failover configuration the interface will run. The valid types for failover are HOT, WARM, and COLD configurations.

If an interface does not supported the requested type of failover, the interface will shutdown and log an error to the pipc.log file stating the requested failover type is not supported.

COLD|WARM|HOT /

COLD

/UFO_Interval=#

Optional

Failover Update Interval Specifies the heartbeat Update

Interval in milliseconds and must be the same on both interface computers.

This is the rate at which UniInt updates the Failover Heartbeat tags as well as how often UniInt checks on the status of the other copy of the interface.

50 - 20000 / 1000

Parameter

Required/ Optional

Description

Value/Default

/Host=server

Required

Host Historian Server for Exceptions and Historian tag updates

The value of the /Host startup parameter depends on the

Historian Server configuration. If the Historian Server is not part of a collective, the value of /Host must be identical on both interface computers.

If the redundant interfaces are being configured to send data to a Historian Server collective, the value of the /Host parameters

on the different interface nodes should equal to different members of the collective.

This parameter ensures that outputs continue to be sent to the Data Source if one of the Historian Servers becomes unavailable for any reason.

For IF-Node1 PrimaryPI / None For IF-Node2 SecondaryPI / None

Point

Description

Value / Default

ActiveID

Monitored by the interfaces to determine which interface is currently sending data to Historian. ActiveID must be initialized so that when the interfaces read it for the first time, it is not an error.

ActiveID can also be used to force failover. For example, if the current Primary is IF-Node 1 and

ActiveID is 1, you can manually change ActiveID to 2. This causes the interface at IF-

Node2 to transition to the primary role and the interface at IF-Node1 to transition to the backup role.

From 0 to the highest Interface Failover ID number / None)

Updated by the redundant Interfaces

Can be changed manually to initiate a manual failover

Heartbeat 1

Updated periodically by the interface on IF-Node1. The interface on IF-Node2 monitors this value to determine if the interface on IF-Node1 has become unresponsive.

Values range between 0 and 31 / None

Updated by the interface on IF-Node1

Heartbeat 2

Updated periodically by the interface on IFNode2. The interface on IF-Node1 monitors this value to determine if the interface on IF-Node2 has become unresponsive.

Values range between 0 and 31 / None

Updated by the interface on IF-Node2

Failover Control Points

The following table describes the points that are required to manage failover. In Phase 2 Failover, these points are located in a data file shared by the Primary and Backup interfaces.

Rockwell Automation recommends that you locate the shared file on a dedicated server that has no other role in data collection. This avoids potential resource contention and processing degradation if your system monitors a large number of data points at a high frequency.

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Attributes

ActiveID

Tag

<Intf>_ActiveID

ExDesc

[UFO2_ActiveID]

Location1

Match # in /id=#

Location5

Optional, Time in minutes to wait for backup to collect data before failing over.

Point Source

Match x in /ps=x

Point Type

Int32

Shutdown

Step

Attribute

Heartbeat 1

Heartbeat 2

DeviceStatus 1

DeviceStatus 2

Tag

<HB1>

<HB2>

<DS1>

<DS2>

ExDesc

[UFO2_Heartbeat:#] Match # in

/UFO_ID=#

[UFO2_Heartbeat:#] Match # in

/UFO_OtherID=#

[UFO2_DeviceStat:#] Match # in

/UFO_ID=#

[UFO2_DeviceStat:#] Match # in

/UFO_OtherID=#

Location1

Match # in /id=#

Location5

Optional, Time in minutes to wait for backup to collect data before failing over.

Point Source

Match x in /ps=x

Match x in /ps=x Point Type

int32

Shutdown

0 0 0

Step

1 1 1

Attribute

Primary

Backup

Tag

DigitalSet

UFO_State

ExDesc

[UFO2_State:#] (Match /UFO_ID=# on primary node)

[UFO2_State:#] (Match /UFO_ID=# on backup node)

Location1

Match # in /id=#

Same as for Primary node

PointSource

Match x in /ps=x

Same as for Primary node

PointType

digital

Shutdown

Step

Historian Tags

The following tables list the required UniInt Failover Control Historian tags, the values they will receive, and descriptions.

Active_ID Tag Configuration

Heartbeat and Device Status Tag Configuration

Interface State Tag Configuration

Historian Tag ExDesc

Required / Optional

Description

Value

[UFO2_ACTIVEID]

Required

Active ID tag The ExDesc must start with the

case sensitive string: [UFO2_ACTIVEID].

The PointSource must match the interfaces‟ point source.

Location1 must match the ID for the interfaces.

Location5 is the COLD failover retry interval in minutes. This can be used to specify how long before an interface retries to connect to the device in a COLD failover configuration. (See the description of COLD failover retry interval for a detailed explanation.)

0 - highest Interface Failover ID

Updated by the redundant Interfaces

[UFO2_HEARTBEAT:#] (IF-Node1)

Required

Heartbeat 1 Tag The ExDesc must start with the

case sensitive string: [UFO2_HEARTBEAT:#]

The number following the colon (:) must be the Failover ID for the interface running on IF-Node1.

The PointSource must match the interfaces‟ point source.

Location1 must match the ID for the interfaces.

0 - 31 / None Updated by the

interface on IF-Node1

[UFO2_HEARTBEAT:#] (IF-Node2)

Required

Heartbeat 2 Tag The ExDesc must start with the

case sensitive string: [UFO2_HEARTBEAT:#]

The number following the colon (:) must be the Failover ID for the interface running on IF-Node2.

The PointSource must match the interfaces‟ point source.

Location1 must match the ID for the interfaces.

0 - 31 / None Updated by the

interface on IF-Node2

The following table describes the extended descriptor for the above Historian tags in more detail.

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Historian Tag ExDesc

Required / Optional

Description

Value

[UFO2_DEVICESTAT :#] (IF-Node1)

Required

Device Status 1 Tag The ExDesc must start with the

case sensitive string: [UFO2_HEARTBEAT:#]

The value following the colon (:) must be the Failover ID for the interface running on IF-Node1

The PointSource must match the interfaces‟ point source.

Location1 must match the ID for the interfaces.

A lower value is a better status and the interface with the lower status will attempt to become the primary interface.

The failover 1 device status tag is very similar to the UniInt Health Device Status tag except the data written to this tag are integer values. A value of 0 is good and a value of 99 is OFF. Any value between these two extremes may result in a failover. The interface client code updates these values when the health device status tag is updated.

0 - 99 / None Updated by the

interface on IF-Node1

[UFO2_DEVICESTAT :#] (IF-Node2)

Required

Device Status 2 Tag The ExDesc must start with the

case sensitive string: [UFO2_HEARTBEAT:#]

The number following the colon (:) must be the Failover ID for the interface running on IF-Node2

The PointSource must match the interfaces‟ point source.

Location1 must match the ID for the interfaces.

A lower value is a better status and the interface with the lower status will attempt to become the primary interface.

0 - 99 / None Updated by the

interface on IF-Node2

[UFO2_STATE:#] (IF-Node1)

Optional

State 1 Tag The ExDesc must start with the

case sensitive string: [UFO2_STATE:#]

The number following the colon (:) must be the Failover ID for the interface running on IF-Node1

The failover state tag is recommended.

The failover state tags are digital tags assigned to a digital state set with the following values.

0 = Off: The interface has been shut down.

1 = Backup No Data Source: The

0 - 5 / None Normally updated

by the interface currently in the primary role.

Historian Tag ExDesc

Required / Optional

Description

Value

interface is running but cannot communicate with the data source.

2 = Backup No Historian Connection: The interface is running and connected to the data source but has lost its communication to the Historian Server.

3 = Backup: The interface is running and collecting data normally and is ready to take over as primary if the primary interface shuts down or experiences problems.

4 = Transition: The interface stays in this state for only a short period of time. The transition period prevents thrashing when more than one interface attempts to assume the role of primary interface.

5 = Primary: The interface is running, collecting data and sending the data to Historian.

[UFO2_STATE:#] (IF-Node2)

Optional

State 2 Tag The ExDesc must start with the

case sensitive string: [UFO2_STATE:#]

The number following the colon (:) must be the Failover ID for the interface running on IF-Node2

The failover state tag is recommended.

Normally updated by the interface currently in the Primary state.

Values range between 0 and 5. See description of State 1 tag.

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Business Network

Process Network

IF-Node1

PI-Interface.exe /host=PrimaryPI /UFO_ID=1 /UFO_OTHERID=2 /UFO_TYPE=HOT /UFO_SYNC=\\FileSvr\UFO\Intf_PS_1.dat

IF-Node2

PI-Interface.exe /host=SecondaryPI /UFO_ID=2 /UFO_OTHERID=1 /UFO_TYPE=HOT /UFO_SYNC=\\FileSvr\UFO\Intf_PS_1.dat

DataSource

DCS/PLC/Data Server

Client

Process Book DataLink

PrimaryPI

PI Server Role = 1

SecondaryPI

PI Server Role = 2

Data register 0

. . .

Data register n

FileSvr

.\UFO\Intf_PS_1.dat

Detailed Explanation of Synchronization through a Shared File (Phase 2)

In a shared file failover configuration, there is no direct failover control information passed between the data source and the interface. This failover scheme uses five Historian tags to control failover operation, and all failover communication between primary and backup interfaces passes through a shared data file.

Once the interface is configured and running, the ability to read or write to the Historian tags is not required for the proper operation of failover. This solution does not require a connection to the Historian Server after initial startup because the control point data are set and monitored in the shared file. However, the Historian tag values are sent to the Historian Server so that you can monitor them with standard Rockwell Automation client tools.

You can force manual failover by changing the ActiveID on the data source to the backup failover ID.

The figure above shows a typical network setup in the normal or steady state. The solid magenta lines show the data path from the interface nodes to the shared file used for failover synchronization. The shared file can be located anywhere in the network as long as both interface nodes can read, write, and create the necessary file on the shared file machine. Rockwell Automation strongly recommends that you put the file on a dedicated file server that has no other role in the collection of data.

The major difference between synchronizing the interfaces through the data source (Phase 1) and synchronizing the interfaces through the shared file (Phase 2) is where the control data is located. When synchronizing through the data source, the control data is acquired directly from the data source. We assume that if the primary interface cannot read the failover control

points, then it cannot read any other data. There is no need for a backup communications path between the control data and the interface.

When synchronizing through a shared file, however, we cannot assume that loss of control information from the shared file implies that the primary interface is down. We must account for the possible loss of the path to the shared file itself and provide an alternate control path to determine the status of the primary interface. For this reason, if the shared file is unreachable for any reason, the interfaces use the Historian Server as an alternate path to pass control data.

When the backup interface does not receive updates from the shared file, it cannot tell definitively why the primary is not updating the file, whether the path to the shared file is down, whether the path to the data source is down, or whether the interface itself is having problems. To resolve this uncertainty, the backup interface uses the path to the Historian Server to determine the status of the primary interface. If the primary interface is still communicating with the Historian Server, than failover to the backup is not required. However, if the primary interface is not posting data to the Historian Server, then the backup must initiate failover operations.

The primary interface also monitors the connection with the shared file to maintain the integrity of the failover configuration. If the primary interface can read and write to the shared file with no errors but the backup control information is not changing, then the backup is experiencing some error condition. To determine exactly where the problem exists, the primary interface uses the path to Historian to establish the status of the backup interface. For example, if the backup interface controls indicate that it has been shutdown, it may have been restarted and is now experiencing errors reading and writing to the shared file. Both primary and backup interfaces must always check their status through Historian to determine if one or the other is not updating the shared file and why.

Steady State Operation

Steady state operation is considered the normal operating condition. In this state, the primary interface is actively collecting data and sending its data to Historian. The primary interface is also updating its heartbeat value; monitoring the heartbeat value for the backup interface, checking the active ID value, and checking the device status for the backup interface every failover update interval on the shared file. Likewise, the backup interface is updating its heartbeat value; monitoring the heartbeat value for the primary interface, checking the active ID value, and checking the device status for the primary interface every failover update interval on the shared file. As long as the heartbeat value for the primary interface indicates that it is operating properly, the ActiveID has not changed, and the device status on the primary interface is good, the backup interface will continue in this mode of operation.

An interface configured for hot failover will have the backup interface actively collecting and queuing data but not sending that data to Historian. An interface for warm failover in the backup role is not actively collecting data from the data source even though it may be configured with Historian tags and may even have a good connection to the data source. An interface configured for cold failover in the backup role is not connected to the data source and upon initial startup will not have configured Historian tags.

The interaction between the interface and the shared file is fundamental to failover. The discussion that follows only refers to the data written to the shared file. However, every value written to the shared file is echoed to the tags on the Historian Server. Updating of the tags on the Historian Server is assumed to take place unless communication with the Historian Server

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is interrupted. The updates to the Historian Server will be buffered by Bufserv or PIBufss in this case.

In a hot failover configuration, each interface participating in the failover solution will queue three failover intervals worth of data to prevent any data loss. When a failover occurs, there may be a period of overlapping data for up to 3 intervals. The exact amount of overlap is determined by the timing and the cause of the failover and may be different every time. Using the default update interval of 5 seconds will result in overlapping data between 0 and 15 seconds. The no data loss claim for hot failover is based on a single point of failure. If both interfaces have trouble collecting data for the same period of time, data will be lost during that time.

As mentioned above, each interface has its own heartbeat value. In normal operation, the Heartbeat value on the shared file is incremented by UniInt from 1 - 15 and then wraps around to a value of 1 again. UniInt increments the heartbeat value on the shared file every failover update interval. The default failover update interval is 5 seconds. UniInt also reads the heartbeat value for the other interface copy participating in failover every failover update interval. If the connection to the Historian Server is lost, the value of the heartbeat will be incremented from 17 - 31 and then wrap around to a value of 17 again. Once the connection to the Historian Server is restored, the heartbeat values will revert back to the 1 - 15 range. During a normal shutdown process, the heartbeat value will be set to zero.

During steady state, the ActiveID will equal the value of the failover ID of the primary interface. This value is set by UniInt when the interface enters the primary state and is not updated again by the primary interface until it shuts down gracefully. During shutdown, the primary interface will set the ActiveID to zero before shutting down. The backup interface has the ability to assume control as primary even if the current primary is not experiencing problems. This can be accomplished by setting the ActiveID tag on the Historian Server to the ActiveID of the desired interface copy.

As previously mentioned, in a hot failover configuration the backup interface actively collects data but does not send its data to Historian. To eliminate any data loss during a failover, the backup interface queues data in memory for three failover update intervals. The data in the queue is continuously updated to contain the most recent data. Data older than three update intervals is discarded if the primary interface is in a good status as determined by the backup. If the backup interface transitions to the primary, it will have data in its queue to send to Historian. This queued data is sent to Historian using the same function calls that would have been used had the interface been in a primary state when the function call was received from UniInt. If UniInt receives data without a timestamp, the primary copy uses the current Historian Time to timestamp data sent to Historian. Likewise, the backup copy timestamps data it receives without a timestamp with the current Historian Time before queuing its data. This preserves the accuracy of the timestamps.

Failover Configuration Using ICU

The use of the ICU is the recommended and safest method for configuring the interface for UniInt failover. With the exception of the notes described in this section, the interface shall be configured with the ICU as described in the Configuring the interface with ICU section of this manual.

Note: With the exception of the /UFO_ID and /UFO_OtherID startup command- line parameters, the UniInt failover scheme requires that both copies of the interface have identical startup command files. This requirement causes the ICU to produce a message when creating the second copy of the interface stating that the “PS/ID combo already in use by the interface” as shown in Figure 5 below. Ignore this message and click the Add button.

Create the interface Instance with ICU

If the interface does not already exist in the ICU it must first be created. The procedure for doing this is the same as for non-failover interfaces. When configuring the second instance for UniInt Failover the Point Source and Interface ID will be in yellow and a message will be displayed saying this is already in use. This should be ignored.

Figure 5: ICU configuration screen shows that the “PS/ID combo is already in use by the

interface.” The user must ignore the yellow boxes, which indicate errors, and click the

Add button to configure the interface for failover.

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Configuring the UniInt Failover Startup Parameters with ICU

There are three interface startup parameters that control UniInt failover: /UFO_ID,

/UFO_OtherID, and /UFO_Interval. The UFO stands for UniInt Failover. The /UFO_ID

and /UFO_OtherID parameters are required for the interface to operate in a failover configuration, but the /UFO_Interval is optional. Each of these parameters is described in detail in Configuring UniInt Failover through a Shared File (Phase 2) section and Start-Up

Parameters.

Figure 6: The figure above illustrates the ICU failover configuration screen showing the UniInt failover startup parameters (Phase 2). This copy of the interface defines its Failover ID as 2 (/UFO_ID=2) and the other interfaces Failover ID as 1 (/UFO_OtherID=1). The other failover interface copy must define its Failover ID as 1 (/UFO_ID=1) and the other interface Failover ID as 2 (/UFO_OtherID=2) in its ICU failover configuration screen. It also defines the location and name of the synchronization file as well as the type of failover as COLD.

Creating the Failover State Digital State Set

The UFO_State digital state set is used in conjunction with the failover state digital tag. If the UFO_State digital state set has not been created yet, it can be using either the Failover page of the ICU (1.4.1.0 or greater) or the Digital States plug-in in the SMT 3 Utility (3.0.0.7 or greater).

Using the ICU Utility to create Digital State Set

To use the UniInt Failover page to create the UFO_State digital state set right-click on any of the failover tags in the tag list and then select the Create UFO_State Digital Set on Server XXXXXX…, where XXXXXX is the Historian Server where the points will be or are create on.

This choice will be grayed out if the UFO_State digital state set is already created on the XXXXXX Historian Server.

Using the SMT 3 Utility to create Digital State Set

Optionally, Export UFO_State Digital Set (.csv) can be selected to create a comma separated file to be imported via the System Management Tools (SMT3) (version 3.0.0.7 or higher) or use the UniInt_Failover_DigitalSet_UFO_State.csv file included in the installation kit.

The procedure below outlines the steps necessary to create a digital set on a Historian Sever using the “Import from File” function found in the SMT3 application. The procedure assumes the user has a basic understanding of the SMT3 application.

1. Open the SMT3 application.

2. Select the appropriate Historian Server from the Historian Servers window. If the

desired server is not listed, add it using the Connection Manager. A view of the SMT application is shown in Figure 7 below.

3. From the System Management Plug-Ins window, select Points then Digital States. A

list of available digital state sets will be displayed in the main window for the selected Historian Server. Refer to Figure 7 below.

4. In the main window, right-click on the desired server and select the Import from File

option. Refer to Figure 7 below.

FactoryTalk Historian To Historian Interface User Guide 93

UniInt Failover Configuration

Figure 7: SMT application configured to import a digital state set file. The Historian Servers window shows the “localhost” Historian Server selected along with the System Management Plug-Ins window showing the Digital States Plug-In as being selected. The digital state set file can now be imported by selecting the Import from File option for the localhost.

5. Navigate to and select the UniInt_Failover_DigitalSet_UFO_State.csv file

for import using the Browse icon on the display. Select the desired Overwrite Options. Click on the OK button. Refer to Figure 8 below.

Figure 8: SMT application Import Digital Set(s) window. This view shows the

UniInt_Failover_DigitalSet_UFO_State.csv file as being selected for import.

Select the desired Overwrite Options by choosing the appropriate radio button.

6. The UFO_State digital set is created as shown in Figure 9 below.

Rockwell Automation FactoryTalk Historian SE 3.0 User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual

Table of Contents

Chapter 1. Introduction

Interface Limitations

Interface Requirements

Reference Manuals

Rockwell Automation

Supported Operating Systems

Supported Features

APS Connector

Supports Questionable Bit

Uses PI SDK

Maximum Point Count

Source of Timestamps

History Recovery

UniInt-based

SetDeviceStatus

Failover

Device Point Types

Diagram of Hardware Connection

Chapter 2. Principles of Operation

Interface Startup

How FactoryTalk Historian to Historian Finds Source Points

Data Collection

History Recovery

Exception Data Collection

Maximizing Data Throughput

Archive Data Collection

Performance Considerations

Load Distribution

Scan Rates

Data Timestamps

Data Type Conversions

Interface Status Events

Adding, Removing and Editing Tags

Error Handling

Source Historian Server-Level Failover

Fault Conditions

Communication Failure

Detection of Stale Data

UniInt Failover

Interface Status Tags

Internal State Status

Failover Status

Deployment Scenarios

Historian to Historian within a Historian Collective

Tag Attribute Override Parameters

Example Architecture for Historian to Historian within a Historian Collective

Firewall Considerations

Historian to Historian between Historian Collectives

Limitations

Historian Collective Support

Data Latency and Source Historian Server Failover

UniInt Failover

Chapter 3. Installation Checklist

Data Collection Steps

Interface Diagnostics

Advanced Interface Features

Chapter 4. Interface Installation

Naming Conventions and Requirements

When Configuring the interface Manually

Interface Directories

PIHOME Directory Tree

Interface Installation Directory

Interface Installation Procedure

Installing Interface as a Windows Service

Installing Interface Service with Historian Interface Configuration Utility

Service Configuration

Service name

Display name

Log on as

Password

Confirm password

Dependencies

- Add Button

- Remove Button

Startup Type