HP C9578-90030 User Manual

hp surestore interface manager

installation and service guide

Part Number: C9578-90030

Edition 1

December 2001

© 2001 Hewlett-Packard Company

Typographical conventions and terms

Bold: Menu choices and screens on the library.

[Bold]: Soft keys to press on the library.

Computer: Host and SCSI commands.

Emphasis: Draws attention to items within text.

This table format indicates the menus you need to enter on the library front panel:

Edit -> Create -> SCSI-II Library

Note	Notes explain significant concepts or
	operating instructions.

Caution Cautions call attention to an operating procedure or practice that could damage the product if not correctly performed. Do not proceed until you understand and meet these required conditions.

WARNING Warnings call attention to a procedure or practice that could result in personal injury if not correctly performed. Do not proceed until you fully understand and meet the required conditions.

In this manual

Chapter 1	Introduction: Describes the
	operation of the Interface
	Manager, as well as components
	and supported products.
Chapter 2	Overview: Provides an overview
	of the configuration options.
Chapter 3	Installation: Describes how to
	install the interface manager, as
	well as power distribution,
	connections and configurations.
Chapter 4	Management Operations:
	Describes the management
	operations, system utilities and
	statistics, diagnostics and trace
	history.
Chapter 5	SAN Environments: Provides an
	overview of Storage Area
	Networks.
Chapter 6	Removing and Replacing Parts:
	Describes how to remove and
	replace field replaceable units.
Chapter 7	Troubleshooting: Describes the
	troubleshooting process, as well as
	problem-solution scenarios.
Appendix A	DB-9 Serial and RJ-45 Ethernet
	Pin Assignment
Appendix B	Fibre Channel Interface and
	Commands
Appendix C	SCSI Interface and Commands
Appendix D	Customer Support

2

Typographical conventions and terms

hp surestore interface manager

Notice

This document contains information that is protected by copyright. All rights are reserved. No part of this document may be photocopied, reproduced, or translated into another language. The information contained in this document is subject to change without notice.

Warranty

Note	See Appendix D for more
	information about service and support.

HP Product: HP Surestore Interface Manager Duration of limited warranty: One Year

1.HP warrants HP hardware, accessories, and supplies against defects in materials and workmanship for the period specified above. If Hewlett-Packard receives notice of such defects during the warranty period, Hewlett-Packard will, at its option, either repair or replace products which prove to be defective. Replacement products may be either new or like-new.

2.HP warrants that HP software will not fail to execute its programming instructions, for the period specified above, due to defects in material and workmanship when properly installed and used. If HP receives notice of such defects during the warranty period, HP will replace software media that does not execute its programming instructions due to such defects.

3.HP does not warrant that the operation of HP products will be uninterrupted or error free. If HP is unable, within a reasonable time, to repair or replace any product to a condition as warranted, customer will be entitled to a refund of the purchase price upon prompt return of the product.

4.HP products may contain remanufactured parts equivalent to new in performance or may have been subject to incidental use.

5.The warranty period begins on the date of delivery or on the date of installation if installed by HP. If customer schedules or delays HP installation more than 30 days after delivery, warranty begins on the 31st day from delivery.

6.Warranty does not apply to defects resulting from

(a) improper or inadequate maintenance or calibration, (b) software, interfacing, parts or supplies not supplied by HP, (c) unauthorized modification or misuse, (d) operation outside of the published environmental specifications for the products, or (e) improper site preparation or maintenance.

7.TO THE EXTENT ALLOWED BY LOCAL LAW, THE ABOVE WARRANTIES ARE EXCLUSIVE AND NO OTHER WARRANTY OR CONDITION, WHETHER WRITTEN OR ORAL, IS EXPRESSED OR IMPLIED AND HP SPECIFICALLY DISCLAIMS ANY IMPLIED WARRANTIES OR CONDITIONS OF MERCHANTABILITY, SATISFACTORY QUALITY, AND FITNESS FOR A PARTICULAR PURPOSE.

8.HP will be liable for damage to tangible property per incident up to the greater of $300,000 or the actual amount paid for the product that is the subject of the claim, and for damages for bodily injury or death, to the extent that all such damages are determined by a court of competent jurisdiction to have been directly caused by a defective HP product.

9.TO THE EXTENT ALLOWED BY LOCAL LAW, THE REMEDIES IN THIS WARRANTY STATEMENT ARE THE CUSTOMER’S SOLE AND EXCLUSIVE REMEDIES. EXCEPT AS INDICATED ABOVE, IN NO EVENT WILL HP OR ITS SUPPLIERS BE LIABLE FOR LOSS OF DATA OR FOR DIRECT, SPECIAL, INCIDENTAL, CONSEQUENTIAL (INCLUDING LOST PROFIT OR DATA), OR OTHER DAMAGE, WHETHER BASED IN CONTRACT, TORT, OR OTHERWISE.

hp surestore interface manager

Notice

3

Reference Standards

■Fibre Channel Physical and Signaling Interface

(FC-PH), ANSI X3T9.3/Project 755D/Rev. 4.3, Contact: Global Engineering, 1-800-854-7179.

■Fibre Channel Protocol for SCSI (FCP) Rev. 12

■Fibre Channel Private Loop Direct Attach (FCPLDA).

■Fibre Channel Arbitrated Loop (FC-AL), ANSI X3T11/Project 960D/ Rev. 4.54, Contact: Global Engineering, 1-800-854-7179.

■Gigabit Interface Converter (GBIC), Small for Factor, SFF-8053, Rev. 5.X.

■Common FC-PH Feature Sets Profiles, Fibre Channel Systems Initiative, FCSI-101-Rev. 3.1.

■SCSI Profile, Fibre Channel System Initiatives, FCSI-201-Rev. 2.2.

■FCSI IP Profile, Fibre Channel System Initiative, FCSI-202-Rev. 2.1.

■ANSI Document T10/99-143 r1 www.t10.org.

4

Reference Standards

hp surestore interface manager

contents

	Typographical conventions and terms 2
	In this manual 2
	Notice 3
	Warranty 3
	Reference Standards 4
Chapter 1	Introduction 11
	Chapter Overview 11
	How the Interface Manager (IM) Works 12
	Processing SCSI Information 14
	Interface Manager (IM) Features 15
	Fibre Channel Features 15
	SCSI Bus Features 15
	Configuration Features 15
	Management Features 16
	Interface Manager (IM) Components 17
	Supplied Components for the Interface Manager 17
	Specifications 19
	Physical Specifications of the Interface Manager (IM) 19
	Environmental Specifications 19
	Supported Products 20
	Optical Fibre Channel Cables 22
Chapter 2	Interface Manager Overview 23
	Chapter Overview 23
	Overview of the Interface Manager (IM) Configuration 24
	Choosing the Right Configuration 25
	Fibre Channel Port Mode 28
	Fibre Channel Arbitrated Loop Addressing 29

5

Hard Addressing 29

Soft Addressing 29

Host Device Configuration 30

SCSI Addressing 30

Buffered Tape Writes 30

Address Mapping 31

Auto-Indexed Mapping 32

Fixed-Indexed Mapping 32

	Configuration Methods 33
	Serial 33
	Ethernet 33
	Telnet 33
	Web Based Administrator 34
Chapter 3	Installation 35
	Chapter Overview 35
	Supported Products 36
	Overview of Installation: CE (Customer Engineer) Installation 37
	Location 37
	Interface Manager Components 38
	Installing the Interface Manager 39
	Attaching the Mounting Rails 41
	Attaching the Flush Mount Brackets 46
	Installing the Power Distribution Unit (PDU) 48
	Installing Fibre Channel (FC) Interface Cards 50
	Fibre Channel Interface Card Installation 51
	Interface Manager SCSI Cable Connections 52
	Installing SCSI Cables 52
	Connecting the Library Controller 57
	Setting Up Serial Port Communications 58
	Powering on the Interface Manager 60
	Powering on the System 60
	Power-On Sequence for the Interface Manager 60
	Power-Up Messages 62
	Initial Configuration of the Remote Management Card (RMC) 64
	Network Access 65
	Configuring the Interface Manager 66

6

Chapter 4	Management Operations 69
	Chapter Overview 69
	Management Interfaces 70
	Serial 70
	Ethernet 70
	Telnet 70
	Web Based Administrator 71
	FTP 71
	Configuration Using the Telnet Interface 72
	Overview 72
	Accessing Telnet 72
	Changing the Administration Password Using Telnet 74
	Changing the Clock Setting Using Telnet 74
	Changing the Ethernet Configuration Using Telnet 76
	Changing the Fibre Channel Address Modes Using Telnet 76
	Hard Addressing 77
	Soft Addressing 78
	Using Your Own Settings 78
	Placing a Fibre Channel Interface Card Off-Line Using Telnet 79
	Placing a Fibre Channel Interface Card On-Line Using Telnet 81
	Installing a New Fibre Channel Interface Card Using Telnet 83
	Changing a Fibre Channel Interface Card Configuration Using Telnet 85
	Choosing Which Card to be Configured 85
	Factory Defaults for the Fibre Channel Interface Card 86
	Configuration Using the Web Based Administrator 87
	Overview 87
	Accessing the Web Based Administrator 89
	Making Changes via the Web Interface 90
	Changing the Clock Setting Using the Web Administrator 90
	Setting Date and Time 90
	Time Shown is NOT Correct 91
	Setting a Time That is Different From the Time Shown 92
	Changing the Ethernet Configuration Using the Web Administrator 92
	Using DHCP 93
	Not Using DHCP 94
	Changing the FC Address Modes Using the Web Administrator 94
	Hard Address Settings 96
	Soft Address Settings 96

7

Selecting Your Own Settings 97

Placing a FC Interface Card Off-Line Using the Web Administrator 98

Placing a FC Interface Card On-Line Using the Web Administrator 101

Installing a New Interface Card Using the Web Administrator 104

Download a New Revision of the Firmware 106

	Using the Web Interface 106
	FTP Interface (All Cards)- Customer Engineer (CE) Only 108
	Upgrade Firmware Using FTP 108
	FTP Interface (Single Card) 109
	Upgrade Firmware Using FTP 109
Chapter 5	SAN Environments 111
	Chapter Overview 111
	Installation and Configuration 112
	Omniback Configuration 115
	HP-UX Configuration 119
	Stopping the dm_stape process 122
	Preventing dm_stape from polling 125
	Windows Configuration 126
	Windows 2000 Removable Storage Manager 126
	Solaris Configuration 128
	Switch Configuration 129
	HP/Brocade Switch and Interface Manager Configuration 129
	FC-64 Director (McData) Switch 130
Chapter 6	Troubleshooting 131
	Chapter Overview 131
	Troubleshooting 132
	Operation Indicators 133
	Basic Verification 137
	LED Indicators 137
	Verify SCSI Bus Configuration 137
	Verify Fibre Channel (FC) Connection 138
	Verify SCSI Devices in Windows NT 138
	Verify Device Recognition in HP-UX 138
	Verify Configuration 140
	Verify Devices 140

8

Verify Host Configuration 140

Verify HBA Device Driver Information 140

Serial Port Problems 140

Customer Support 141

Problem - Solution 142

Problem: Drives Not Detected after Power Failure 142

Option 1	- Not Using Telnet or the Web Interface 142
Option 2	- Using Telnet 142
Option 3	- Using the Web Interface 142

	Problem: Cannot Turn on the Interface Manager 143
	Problem: Cannot Confirm the Library Connection (Windows NT ) 143
	Problem: Cannot Confirm Connection Through a Fibre Channel Switch 145
	Problem: Cannot Confirm the Library Connection (HP-UX ) 145
Chapter 7	Removing and Replacing Parts 149
	Chapter Overview 149
	Field Replaceable Units (FRUs) 150
	Replacing the Interface Manager Chassis 152
	Removing and Replacing the Remote Management or Controller Card 153
	Removing Cards: Remote Management (RMC), and Controller 154
	Replacing a Card: Remote Management (RMC), and Controller 154
	Removing and Replacing a Fibre Channel Interface Card 156
	Removing a Fibre Channel Interface Card 156
	Replacing a Fibre Channel Card 157
	Removing and Replacing the Redundant Power Supply 158
	Removing Individual Power Supply Units 158
	Replacing the Redundant Power Supply Module 159
	Removing a Fan 161
	Replacing a Fan 162
	Upgrading Firmware 163
	Checking the Firmware Revision 163
	Using a Host Diagnostic Utility 164
	Using HP Library & Tape Tools (Windows only) 164
	Using Support Tools Manager (HP-UX and MPE/iX only) 164

9

Appendix A	DB-9 Serial and RJ-45 Ethernet Pin Assignment 165
	Serial and Ethernet Assignment 165
Appendix B	Fibre Channel Interface and Commands 167
	Download Commands 167
	Upgrade Firmware 167
	Report LUNs Command 169
	PRLI Data 171
Appendix C	SCSI Interface and Commands 173
	SCSI Inquiry Data 173
Appendix D	Customer Support 175
	Registering Your Product 175
	Backup Software Support 175
	Hewlett-Packard Customer Support 176
	Information Needed for Support 176

10

Introduction	1

Chapter Overview

This chapter contains information on the following:

■How the Interface Manager (IM) Works on page 12

■Processing SCSI Information on page 14

■Interface Manager (IM) Features on page 15

■Interface Manager (IM) Components on page 17

■Specifications on page 19

■Supported Products on page 20

Introduction 11

How the Interface Manager (IM) Works

The IM provides connectivity between a Fibre Channel (FC) switched fabric (FC-SW) or Fibre Channel arbitrated loop (FC-AL) and up to 20 Ultra-2 SCSI buses.

The IM contains slots for up to eleven (one slot is reserved for future expansion) Fibre Channel cards. Each card connects a FC port to two Ultra-2 SCSI ports. The IM also contains a Remote Management Card (RMC) in slot 1, and a controller card in slot 2. The RMC provides the user with a serial port for initial setup, as well as Telnet and Web Administrator - HTTP access to any of the cards in the IM.

Each FC card translates the FC protocol (FCP) to and from the SCSI protocol so that FC and SCSI devices can communicate. The FC card attaches to a FC host, hub, or switch and transfers the command, data, and status information to SCSI targets. Packets are transferred transparently by the IM between a host and targets and vice versa.

SCSI and Fibre Channel connectors are accessed from the front of the IM. Ethernet and serial ports provide the means for configuring and managing the IM. A power connector is located on the front of the Interface Manager.

12 Introduction

Chapter 1

Figure 1 shows the front view of the Interface Manager.

Figure 1 Front View of the Interface Manager

Table 1 Features of the Interface Manager

Number	Part
1	Serial DB-9 connector for terminal access
2	Ethernet RJ-45 connector for FTP, Telnet and Web browser access
3	Remote management card
4	Controller card
5	Slots for Fibre Channel interface cards
6	Reserved slot
7	Redundant power supply

1 Chapter

Chapter 1

Introduction 13

Processing SCSI Information

The following section describes how the Interface Manager (IM) processes SCSI information when attached to Fibre Channel (FC) hosts.

1.A FC host issues a command. The FC host encapsulates the SCSI command in the FC protocol and sends the packet to the IM.

2.The FC card in the IM receives the packet, interprets the FC information, and places the packet in buffer memory.

3.The IM’s processor interprets the information and programs a SCSI controller to process the transaction.

4.The SCSI controller sends the command to the SCSI device (target).

5.The SCSI target interprets the command and executes it.

6.Data flows between the FC host and SCSI target through payload buffers.

7.Response information flows from the SCSI target back to the FC host.

14 Introduction

Chapter 1

Interface Manager (IM) Features

Fibre Channel Features

■Fibre Channel target mode

■Single 1.0625 Gbps FC port

■Fibre Channel arbitrated loop (FC-AL) and switched fabric (FC-SW) topologies, includes point-to-point (PPP) configurations

■Private Loop Direct Attach (PLDA) profile compliant

■Class 3 connection with SCSI-FCP protocol

■Supports FCP-2 error recovery protocol as specified in FCP-2 rev. 03 for use with streaming devices (such as tape) and medium changers

SCSI Bus Features

■SCSI initiator mode

■Up to 20 auto-negotiating SCSI buses (Narrow, Wide, Fast, Ultra)

■Ultra-2 wide SCSI for data transfer up to 80MB/s per bus (LVD)

■Ultra-2 wide SCSI for data transfer up to 40MB/s per bus (HVD)

■SCSI-2 and SCSI-3 protocols

■Differential or LVD/single-ended internal termination (HVD or LVD Single-ended)

■Supports tape and medium changer SCSI devices

Configuration Features

■DHCP for easier network administration

■Serial DB-9 connector for terminal access

■Ethernet RJ-45 connector for FTP, Telnet and Web browser access

■Field-upgradeable firmware

1 Chapter

Chapter 1

Introduction 15

Management Features

■Out-of-band Ethernet TCP/IP management access

■In-Band management

16 Introduction

Chapter 1

Interface Manager (IM) Components

This section includes a list of all parts supplied with the IM.

Supplied Components for the Interface Manager

Figure 2 Supplied Components

1 Chapter

Chapter 1

Introduction 17

Table 2		Supplied Components
No.		Item	Qty	Description
1		HP Surestore Interface Manager	1	Base Product: Chassis, Interface Manager controller,
				remote management card, power supply and three fans
2		Mounting rails	2	Left and right mounting rails
3		Mounting rail extensions	2	Used for the 10/180 tape library only
4		Hardware identification board	1	Hardware consisting of:
				6 - 10x32 hex nuts
				12 - sheet metal nuts
				16 - 10x32 x 50 machine screws
5		Flush mount brackets	2	Left and right flush mount brackets
6		Cable labeling kit	1	Label kit to label the SCSI and fibre cables
7		Power distribution unit	1	Power distribution unit
8		HP Surestore Interface Manager	1	Installation and Cabling Poster
		Installation and Cabling Poster
9		HP Surestore Interface Manager	1	User’s Guide
		User’s Guide
10		Serial cable	1	Serial cable
11		Power cord	1	power cord (PDU to the Interface Manager)
12		SCSI cable	1	2.5 meter FC SCSI cable for daisy chaining the robotics to
				a drive - High Density - Do not use with the Interface
				Manager
13		Localized power cord	1	Localized power cord (wall to PDU)

18 Introduction

Chapter 1

Specifications

This section includes information on the physical and environmental specifications for the Interface Manager.

Physical Specifications of the Interface Manager (IM)

The IM is installed inside the accessory bin of the 10/180 and 20/700 HP tape libraries.

The physical characteristics are as follows:

Table 3 Physical Specifications of the Interface Manager

Height	8.48 inches (21.2 cm)
Width	17.26 inches (43.15 cm)
Depth	10.78 inches (26.95 cm)
Weight (to include box with fans,	Approximately 34.2 pounds
redundant power supply, Interface	(15.54 kg)
Manager controller and RMC boards and
11 slot covers)

Environmental Specifications

Choose a location that meets the following criteria:

Table 4 Location Criteria

Room temperature	50o - 95o Farenheit (10o - 35o C)
Humidity	20% to 80% relative humidity, non-condensing
Power source	AC power voltage: 100-127 VAC/200-240VAC
	50-60 Hz

1 Chapter

Chapter 1

Introduction 19

Supported Products

Table 5 shows the products that Hewlett-Packard supports for connection with the Interface Manager:

Table 5 Supported Products

Description	Product
HP SureStore E Tape Libraries:	10/180 - A5617A
10/180 and 20/700 with Ultrium,	20/700 - A5597A, A5597B
DLT 7000, DLT 8000, and 9840 tape
drives
HP Fibre Channel Switches	Brocade SilkWorm 2800 - A5624A
	Brocade SilkWorm 2400 - A5625A
QLogic Fibre Channel HBA	Win NT 4.0, Windows 2000, Netware 5.x - QLA-2200F
Emulex HBA	Win NT 4.0, Windows 2000 - LP8000-N1, LP8000-F1
Compaq HBA	Win NT 4.0, Windows 2000 - 176479-B21

20 Introduction

Chapter 1

Table 5 Supported Products

Description			Product
HP Fibre Channel Host Bus Adapters		HP-UX 11.11,11.0 A5158A (pci)
		HP-UX 11.11,11.0, 10.20 A6685A (hsc-K class), A6684A
		(hsc-D, R class)
		A6684A and A6685A adapters are only supported on the
		following R, D, and K-class servers:
		A6684A Supported Platforms:
		R-class	R380.R390
		D-class	D220.D230/D320/D330
			D270/D280/D370/D380/D390
		A6685A Supported Platforms:
		K-class	K220/K420/K250/K450/K260/K360/
			K370/K380/K460/K570/K580
		HP-UX 11.0; V, N & L Class - A5158A
		HP-UX 10.20 & 11.0; T600 - A3636A
		HP-UX 10.20 & 11.0; D & R Class - A3591B
		HP-UX 10.20 & 11.0; K Class - A3404A
		Win NT 4.0, Windows 2000 - D8602A
		Win NT 4.0 SP 4 & above; HP Netserver - D8602A/B
		Win NT 4.0 SP 4 & above; Compaq Proliant - D8602A/B
		Win NT 4.0 SP 4 & above; Dell PowerEdge - D8602A/B
		Win NT 4.0 SP 4 & above; IBM Netfinity - D8602A/B
Sun Solaris 2.6, 7, 8		JNI FC64-1063N (sbus)
		JNI FCI-1063 (pci)
		JNI FCE-1063-N (sbus)
		FCE-6410-N (pci)
	Note	DLT 7000 tape drives are only supported in the 20/700 tape
		library.

1 Chapter

Chapter 1

Introduction 21

Note The A3636A, A3591B and the A3404A FC HBA are only supported in point-to-point (PPP) configurations (not through a switch).

Note HVD SCSI tape drives (DLT 7000, DLT 8000, 9840, and the HVD version of Ultrium) should only be attached to HVD SCSI ports on the Interface Manager.

Optical Fibre Channel Cables

The Interface Manager uses the following fiber-optic cables available in the lengths listed in Table 6.

Table 6 Fibre-Optic Cable Lengths

Product Number	Length
A3583A FC Optical Cable	2 meters
A3531A FC Optical Cable	16 meters
A3735A FC Optical Cable	50 meters
A3736A FC Optical Cable	100 meters
A5225A SW Optical/GBIC	N/A

22 Introduction

Chapter 1

Interface Manager Overview	2

Chapter Overview

This chapter contains information on the following:

■Overview of the Interface Manager (IM) Configuration on page 24

■Choosing the Right Configuration on page 25

Chapter Overview 23

Overview of the Interface Manager (IM) Configuration

The IM can be configured through one of several user interfaces:

■Over a serial port via a terminal or terminal emulation utility

■Over Ethernet via a Telnet utility, Internet Web browser, or SNMP management tool

Note	Before configuring the Interface Manager, a basic understanding
	of Fibre Channel and SCSI devices is recommended.
	For information on SCSI standards, refer to publications from the
	X3T10 committee of ANSI (American National Standards
	Institute). For information on Fibre Channel standards, refer to
	publications from the X3T11 committee of ANSI. Approved
	American National Standards and Technical Reports may be
	purchased from:
	ANSI
	11 West 42nd Street
	13th Floor
	New York, NY 10036
	Sales Department: [phone]

24 Overview of the Interface Manager (IM) Configuration

Chapter 2

Choosing the Right Configuration

The factory default settings of the Interface Manager (IM) permit the type of configuration shown in Figure 3 on page 26 (standard configuration) to work without any initial changes to these settings. The IM settings may need to be changed for expanded configurations (see Figure 4 on page 27) or certain application requirements.

2 Chapter

Chapter 2

Choosing the Right Configuration 25

Figure 3

Example of a Standard Configuration in a 20/700 Tape Library

26 Choosing the Right Configuration

Chapter 2

Figure 4

Expanded Configuration

2 Chapter

Chapter 2

Choosing the Right Configuration 27

A standard configuration may involve several Fibre Channel (FC) hosts connected to multiple FC cards. These FC host systems may be connected to the cards either in a point-to-point (PPP) fashion or through a FC switch. Each card is then connected to two SCSI tape drives.

The library’s robotics controller may be daisy-chained with one of the SCSI tape drives or connected directly to an available FC interface card SCSI port, or direct connect SCSI to host.

Note	When daisy-chaining the library’s robotics controller to any LVD
	tape drive, the library must have the LVD to HVD converter
	(A6324A) installed.

Fibre Channel Port Mode

The IM’s Fibre Channel ports can operate in either NL_Port or N_Port mode. The IM has the ability to autosense and choose between these modes of operation.

■NL_Port - The IM can share a FC Arbitrated Loop with other NL_Port devices (or HBAs). A single FC switch port acting in FL_Port mode can also be connected to the loop.

■N_Port - The IM does not employ the arbitrated loop protocol. This allows for a more efficient connection to a single FC switch port acting in F_Port mode.

Some FC switches (such as the HP/Brocade SilkWorm) support either FL_Port and F_Port modes with autosensing capabilities. Other switches (such as the HP Surestore Director) only support the F_Port mode. When connecting directly to a FC switch port, configure the IM in N_Port mode for a more stable and efficient connection.

Port mode can only be set in the FC Configuration menu via the Telnet interface. See Configuration Using the Telnet Interface on page 38.

28 Choosing the Right Configuration

Chapter 2

Fibre Channel Arbitrated Loop Addressing

On a FC arbitrated loop, each device appears as an Arbitrated Loop Physical Address (AL_PA). To obtain an AL_PA, two methods called soft and hard addressing can be used by the IM. The IM can be configured to use either method.

Hard Addressing

Hard addressing is recommended for FC arbitrated loop environments where it is important that the FC device addresses do not change. Device address changes can affect the mapping represented by the host operating system to the application. An example of such an environment would be a tape library installation, where the application configuration requires fixed device identification for proper operation. Hard addressing ensures that the device identification to the application remains constant.

When acquiring a hard address, the IM attempts to acquire the AL_PA value that was specified by user configuration. If the desired address is not available at loop initialization time, the IM will come up on the FC loop using an available soft address. This allows the loop to continue to operate. This situation would occur when another device on the arbitrated loop has acquired the same address as that configured on the IM.

When connected to a FC switch, the IM is identified to the switch as a unique device by the factory programmed World Wide Name (WWN).

Soft Addressing

Soft addressing is recommended for FC fabric environments where the FC interface card does not employ the Arbitrated Loop protocol. In these environments, an AL_PA is not used as part of the device address, so soft addressing allows the FC interface card to operate as an N_Port. Soft addressing is recommended primarily for switched fabric configurations.

When acquiring a soft address, the FC interface card acquires the first available loop address starting from address 01 and moving up the list of available AL_PAs to EF. In this mode, the FC interface card automatically obtains an available address and participates on the FC loop, as long as there is at least one address available on the loop that is connected to the IM. FC supports up to 126 devices on an arbitrated loop.

2 Chapter

Chapter 2

Choosing the Right Configuration 29

Host Device Configuration

The host system using a FC host bus adapter (HBA) will typically map FC devices into the existing device mapping scheme used by that operating system. (Refer to your HBA manual for the mapping table.) The FC usually maps FC addresses to SCSI target addresses. In such a configuration, the IM corresponds to a bus:target identifier, with the SCSI devices attached to the IM appearing as logical units (LUNs). In addition, operating systems can extend the available SCSI limit of 15 Target IDs per bus.

Although this is not an issue for the operating system or most applications, there are cases where older applications or Windows NT can have expectations about what are valid SCSI IDs, and not deal correctly with certain mappings. In particular, applications have been seen to exhibit difficulties addressing Target IDs greater than 15 (e.g. 16 and up). This problem can be resolved by configuring the IM to use hard addressing, and setting the AL_PA used by the IM to a value that the HBA will map to, with an ID having a value less than 16.

SCSI Addressing

A FC interface card appears on each SCSI bus as a single initiator. The default initiator ID is 7. No other device on the SCSI bus may use this address. Note that the FC host itself is not connected to the bus. Their SCSI operations are passed down to the individual SCSI target devices through the use of the IM’s SCSI Initiator ID.

The IM negotiates for the maximum values for transfer rates and bandwidth on a SCSI bus. If an attached SCSI device does not allow the full rates, the IM will use the best rates it can negotiate for that device. Negotiation is on a device specific basis, so the IM can support a mix of SCSI device types on the same SCSI bus.

Buffered Tape Writes

Buffered Tape Writes is an option designed to enhance system performance. By returning status on consecutive write commands prior to the tape device receiving data, Buffered Tape Writes remove the latency of waiting for responses from the tape device. In the event that data does not transfer correctly for any reason, the interface card will return a check condition on a subsequent command.

30 Choosing the Right Configuration

Chapter 2