Hirschmann RS20, RS30, RS40, MS20, MS30 Redundancy Configuration

UM Redundancy Configuration L2E

Release 7.1 12/2011

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User Manual

Redundancy Configuration
Industrial Ethernet (Gigabit) Switch

RS20/RS30/RS40, MS20/MS30, OCTOPUS

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not be taken to mean that these names may be considered as free in the sense of the trademark
and tradename protection law and hence that they may be freely used by anyone.

© 2011 Hirschmann Automation and Control GmbH

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either in whole or in part. An exception is the preparation of a backup copy of the software for
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enclosed CD applies.

The performance features described here are binding only if they have been expressly agreed
when the contract was made. This document was produced by Hirschmann Automation and
Control GmbH according to the best of the company's knowledge. Hirschmann reserves the right
to change the contents of this document without prior notice. Hirschmann can give no guarantee
in respect of the correctness or accuracy of the information in this document.

Hirschmann can accept no responsibility for damages, resulting from the use of the network
components or the associated operating software. In addition, we refer to the conditions of use
specified in the license contract.

You can get the latest version of this manual on the Internet at the Hirschmann product site
(www.beldensolutions.com).

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72654 Neckartenzlingen
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Tel.: [phone]

Rel 7.1 12/2011 13.12.11

Contents

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Contents

About this Manual 5

Key 7

1 Introduction 9

1.1 Overview of Redundancy Topologies 10

1.2 Overview of Redundancy Protocols 11

2 Ring Redundancy 13

2.1 Example of a HIPER-Ring 15

2.1.1 Setting up and configuring the HIPER-Ring 17

2.2 Example of a MRP-Ring 21

3 Multiple Rings 27

4 Ring/Network Coupling 29

4.1 Variants of the ring/network coupling 30

4.2 Preparing a Ring/Network Coupling 32

4.2.1 Stand-by switch 32

4.2.2 One-Switch coupling 35

4.2.3 Two-Switch coupling 41

4.2.4 Two-Switch Coupling with Control Line 49

5 Spanning Tree 57

5.1 The Spanning Tree Protocol 59

5.1.1 The tasks of the STP 59

5.1.2 Bridge parameters 60

5.1.3 Bridge Identifier 60

5.1.4 Root Path Cost 61

5.1.5 Port Identifier 63

5.2 Rules for Creating the Tree Structure 64

5.2.1 Bridge information 64

5.2.2 Setting up the tree structure 64

5.3 Example of determining the root path 67

5.4 Example of manipulating the root path 69

Contents

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5.5 Example of manipulating the tree structure 71

5.6 The Rapid Spanning Tree Protocol 72

5.6.1 Port roles 72

5.6.2 Port states 74

5.6.3 Spanning Tree Priority Vector 75

5.6.4 Fast reconfiguration 76

5.6.5 Configuring the Rapid Spanning Tree 77

5.7 Combining RSTP and MRP 87

5.7.1 Application example for the combination of RSTP and
MRP 89

A Readers’ Comments 92

B Index 95

C Further Support 97

About this Manual

UM Redundancy Configuration L2E

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5

About this Manual

The “Redundancy Configuration User Manual” document contains the
information you require to select the suitable redundancy procedure and
configure it.

The “Basic Configuration” user manual contains the information you need to
start operating the device. It takes you step by step from the first startup
operation through to the basic settings for operation in your environment.

The “Installation” user manual contains a device description, safety
instructions, a description of the display, and the other information that you
need to install the device.

The “Industry Protocols” user manual describes how the device is connected
by means of a communication protocol commonly used in the industry, such
as EtherNet/IP and PROFINET IO.

The “GUI” reference manual contains detailed information on using the
graphical interface to operate the individual functions of the device.

The “Command Line Interface” Reference Manual contains detailed
information on using the Command Line Interface to operate the individual
functions of the device.

About this Manual

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The Industrial HiVision Network Management Software provides you with
additional options for smooth configuration and monitoring:

 Simultaneous configuration of multiple devices
 Graphic interface with network layout
 Auto-topology discovery
 Event log
 Event handling
 Client/server structure
 Browser interface
 ActiveX control for SCADA integration
 SNMP/OPC gateway.

 Maintenance

Hirschmann are continually working on improving and developing their
software. You should regularly check whether there is a new version of
the software that provides you with additional benefits. You will find
software information and downloads on the product pages of the
Hirschmann website.

Key

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Key

The designations used in this manual have the following meanings:

Symbols used:

 List

 Work step



Subheading

Link Cross-reference with link

Note: A note emphasizes an important fact or draws your attention to a dependency.

Courier ASCII representation in user interface

Execution in the Graphical User Interface (Web-based Interface user interface)
Execution in the Command Line Interface user interface

WLAN access point

Router with firewall

Switch with firewall

Router

Switch

Key

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Bridge

Hub

A random computer

Configuration Computer

Server

PLC ­Programmable logic
controller

I/O ­Robot

Introduction

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1 Introduction

The device contains a range of redundancy functions:

 HIPER-Ring
 MRP-Ring
 Ring/Network coupling
 Rapid Spanning Tree Algorithm (RSTP)

Introduction

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1.1 Overview of Redundancy
Topologies

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1.1 Overview of Redundancy
Topologies

To introduce redundancy onto layer 2 of a network, first clarify which network
topology you require. Depending on the network topology selected, you then
choose from the redundancy protocols that can be used with this network
topology.

The following topologies are possible:

The Ring Redundancy Protocol MRP has particular properties to offer:

 You have the option of coupling to MRP-Rings other ring structures that

work with RSTP (see on page 87 “Combining RSTP and MRP”).

Network topology Possible redundancy

procedures

Comments

Tree structure
without loops
(cycle-free)

Only possible in
connection with
physical loops

-

Topology with 1
loop

RSTP
Ring Redundancy

Ring Redundancy procedures (HIPER-Ring, Fast
HIPER-Ring or MRP) provide shorter switching
times than RSTP.

Topology with 2
loops

RSTP
Ring Redundancy

Ring redundancy: an MRP-Ring with an RSTP­Ring.

Topology with 3
non-nested loops

RSTP
Ring Redundancy
Ring coupling

The ring coupling provides particular support
when redundantly coupling a redundant ring to
another redundant ring, or to any structure that
only works with Hirschmann devices

Table 1: Overview of Redundancy Topologies

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1.2 Overview of

Redundancy Protocols

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1.2 Overview of
Redundancy Protocols

Note: When you are using a redundancy function, you deactivate the flow
control on the participating ports. Default setting: flow control deactivated
globally and activated on all ports.
If the flow control and the redundancy function are active at the same time,
the redundancy may not work as intended.

Redundancy
procedure

Network topology Switch-over time

RSTP Random structure typically < 1 s (STP < 30 s), up to < 30 s - depends

heavily on the number of devices

Note: Up to 79 devices possible, depending on topology and configuration. If
the default values (factory settings) are used, up to 39 devices are possible,
depending on the topology (see page 57).

HIPER-Ring Ring typically 80 ms, up to < 500 ms or < 300 ms (selectable)

- the number of switches has a minimal effect on the
switch-over time

MRP-Ring Ring typically 80 ms, up to < 500 ms or < 200 ms (selectable)

- the number of switches has a minimal effect on the
switch over time

Note: In combination with RSTP in MRP compatibility mode, up to 39 devices
are possible, depending on the configuration. If the default values (factory
settings) for RSTP are being used, up to 19 devices are possible (see page 57).

Table 2: Comparison of the redundancy procedures

Introduction

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1.2 Overview of

Redundancy Protocols

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Ring Redundancy

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2 Ring Redundancy

The concept of ring redundancy allows the construction of high-availability,
ring-shaped network structures.
With the help of the RM (Ring Manager) function, the two ends of a backbone
in a line structure can be closed to a redundant ring. The ring manager keeps
the redundant line open as long as the line structure is intact. If a segment
becomes inoperable, the ring manager immediately closes the redundant
line, and line structure is intact again.

Figure 1: Line structure

Figure 2: Redundant ring structure

RM = Ring Manager
—— main line

- - - redundant line

RM

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If a section is down, the ring structure of a

 HIPER-(HIGH PERFORMANCE REDUNDANCY) Ring with up to 50

devices typically transforms back to a line structure within 80 ms (possible
settings: standard/accelerated).

 MRP (Media Redundancy Protocol) Ring (IEC 62439) of up to 50 devices

typically transforms back to a line structure within 80 ms (adjustable to
max. 200 ms/500 ms).

Devices with HIPER-Ring function capability:

 Within a HIPER-Ring, you can use any combination of the following

devices:
–RS1
– RS2-./.
– RS2-16M
–RS2-4R
– RS20, RS30, RS40
– RSR20, RSR30
– OCTOPUS
–MICE
–MS20, MS30
–PowerMICE
– MACH 100
– MACH 1000
– MACH 1040
– MACH 3000
– MACH 4000

 Within an MRP-Ring, you can use devices that support the MRP protocol

based on IEC62439.

Note: Only one Ring Redundancy method can be enabled on one device at
any one time. When changing to another Ring Redundancy method,
deactivate the function for the time being.

Note: The following usage of the term “ring manager” instead of “redundancy
manager” makes the function easier to understand.

Ring Redundancy

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2.1 Example of a HIPER-Ring

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2.1 Example of a HIPER-Ring

A network contains a backbone in a line structure with 3 devices. To increase
the redundancy reliability of the backbone, you have decided to convert the
line structure to a HIPER-Ring. You use ports 1.1 and 1.2 of the devices to
connect the lines

1

.

Figure 3: Example of HIPER-Ring

RM = Ring Manager
—— main line

- - - redundant line

The following example configuration describes the configuration of the ring
manager device (1). The two other devices (2 to 3) are configured in the
same way, but without activating the ring manager function. Select the
“Standard” value for the ring recovery, or leave the field empty.

1. On modular devices the 1st number of the port designation specifies the

module. The 2nd number specifies the port on the module. The specification
pattern 1.x is also used on non-modular devices for consistency.

RM

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1.1 1.2 1.1 1.2 1.1 1.2

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2.1 Example of a HIPER-Ring

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Note: As an alternative to using software to configure the HIPER-Ring, with
devices RS20/30/40 and MS20/30 you can also use DIP switches to enter a
number of settings on the devices. You can also use a DIP switch to enter a
setting for whether the configuration via DIP switch or the configuration via
software has priority. The state on delivery is “Software Configuration”. You
will find details on the DIP switches in the “Installation” user manual.

Note: Configure all the devices of the HIPER-Ring individually. Before you
connect the redundant line, you must complete the configuration of all the
devices of the HIPER-Ring. You thus avoid loops during the configuration
phase.

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2.1 Example of a HIPER-Ring

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2.1.1 Setting up and configuring the HIPER-Ring

 Set up the network to meet your demands.
 Configure all ports so that the transmission speed and the duplex settings

of the lines correspond to the following table:

Note: When activating the HIPER-Ring function via software or DIP
switches, the device sets the corresponding settings for the pre-defined ring
ports in the configuration table (transmission rate and mode). If you switch off
the HIPER-Ring function, the ports, which are changed back into normal
ports, keep the ring port settings. Independently of the DIP switch setting, you
can still change the port settings via the software.

Port type Bit rate Autonegotiation

(automatic
configuration)

Port setting Duplex

TX 100 Mbit/s off on 100 Mbit/s full duplex (FDX)
TX 1 Gbit/s on on ­Optical 100 Mbit/s off on 100 Mbit/s full duplex (FDX)
Optical 1 Gbit/s on on ­Optical 10 Gbit/s - on 10 Gbit/s full duplex (FDX)

Table 3: Port settings for ring ports

 Select the Redundancy:Ring Redundancy dialog.
 Under “Version”, select HIPER-Ring.
 Define the desired ring ports 1 and 2 by making the corresponding

entries in the module and port fields. If it is not possible to enter a
module, then there is only one module in the device that is taken
over as a default.

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2.1 Example of a HIPER-Ring

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Display in “Operation” field:
– active: This port is switched on and has a link.
– inactive: This port is switched off or it has no link.

Figure 4: Ring Redundancy dialog

 Activate the ring manager for this device. Do not activate the ring

manager for any other device in the HIPER-Ring.
 In the “Ring Recovery” frame, select the value “Standard” (default).
Note: Settings in the “Ring Recovery” frame are only effective for

devices that you have configured as ring managers.

 Click “Set” to temporarily save the entry in the configuration.

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2.1 Example of a HIPER-Ring

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 Now proceed in the same way for the other two devices.

Note: If you have configured VLANS, note the VLAN configuration of the ring
ports.
In the configuration of the HIPER-Ring, you select for the ring ports
– VLAN ID 1 and “Ingress Filtering” disabled in the port table and
– VLAN membership U in the static VLAN table.

Note: Deactivate the Spanning Tree protocol for the ports connected to the
HIPER-Ring, because Spanning Tree and Ring Redundancy affect each
other.

enable Switch to the privileged EXEC mode.
configure Switch to the Configuration mode.
hiper-ring mode ring-manager Select the HIPER-Ring ring redundancy and

define the device as ring manager.

Switch's HIPER Ring mode set to ring-manager
hiper-ring port primary 1/1 Define port 1 in module 1 as ring port 1.

HIPER Ring primary port set to 1/1
hiper-ring port secondary 1/2 Define port 2 in module 1 as ring port 2.
HIPER Ring secondary port set to 1/2
exit Switch to the privileged EXEC mode.
show hiper-ring Display the HIPER-Ring parameters.

HIPER Ring Mode of the Switch.................. ring-manager

configuration determined by.................. management

HIPER Ring Primary Port of the Switch.......... 1/1, state active

HIPER Ring Secondary Port of the Switch........ 1/2, state active

HIPER Ring Redundancy Manager State............ active

HIPER Ring Redundancy State (red. exists).. no (rm is active)

HIPER Ring Setup Info (Config. failure)........ no error

HIPER Ring Recovery Delay...................... 500ms

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2.1 Example of a HIPER-Ring

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If you used the DIP switch to activate the function of HIPER-Ring, RSTP is
automatically switched off.

 Now you connect the line to the ring. To do this, you connect the 2 devices

to the ends of the line using their ring ports.

Note: If you want to use link aggregation connections in the HIPER-Ring
(PowerMICE and MACH 4000), you enter the index of the desired link
aggregation entry for the module and the port.

The displays in the “Redundancy Manager Status” frame mean:
– “Active (redundant line)”: The ring is open, which means that a data

line or a network component within the ring is down.
– “Inactive”: The ring is closed, which means that the data lines and

network components are working.
The displays in the “Information” frame mean

– “Redundancy existing”: One of the lines affected by the function may

be interrupted, with the redundant line then taking over the function

of the interrupted line.
– "Configuration failure”: The function is incorrectly configured or the

cable connections at the ring ports are improperly configured (e.g.,

not plugged into the ring ports).

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2.2 Example of a MRP-Ring

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2.2 Example of a MRP-Ring

A network contains a backbone in a line structure with 3 devices. To increase
the availability of the backbone, you decide to convert the line structure to a
redundant ring. In contrast to the previous example, devices from different
manufacturers are used which do not all support the HIPER-Ring protocol.
However, all devices support MRP as the ring redundancy protocol, so you
decide to deploy MRP. You use ports 1.1 and 2.2 of the devices to connect
the lines.

Figure 5: Example of MRP-Ring

RM = Ring Manager
—— main line

- - - redundant line

The following example configuration describes the configuration of the ring
manager device (1). You configure the 2 other devices (2 to 3) in the same
way, but without activating the ring manager function. This example does not
use a VLAN. You have entered 200 ms as the ring recovery time, and all the
devices support the advanced mode of the ring manager.

RM

12 3

1.1 1.2 1.1 1.2 1.1 1.2

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2.2 Example of a MRP-Ring

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Note: For devices with DIP switches, put all DIP switches to “On”. The effect
of this is that you can use the software configuration to configure the
redundancy function without any restrictions. You thus avoid the possibility of
the software configuration being hindered by the DIP switches.

Note: Configure all the devices of the MRP-Ring individually. Before you
connect the redundant line, you must have completed the configuration of all
the devices of the MRP-Ring. You thus avoid loops during the configuration
phase.

 Set up the network to meet your demands.
 Configure all ports so that the transmission speed and the duplex settings

of the lines correspond to the following table:

Port type Bit rate Autonegotiation

(automatic
configuration)

Port setting Duplex

TX 100 Mbit/s off on 100 Mbit/s full duplex (FDX)
TX 1 Gbit/s on on ­Optical 100 Mbit/s off on 100 Mbit/s full duplex (FDX)
Optical 1 Gbit/s on on ­Optical 10 Gbit/s - on 10 Gbit/s full duplex (FDX)

Table 4: Port settings for ring ports

 Select the Redundancy:Ring Redundancy dialog.
 Under “Version”, select MRP.
 Define the desired ring ports 1 and 2 by making the corresponding

entries in the module and port fields. If it is not possible to enter a

module, then there is only one module in the device that is taken

over as a default.

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2.2 Example of a MRP-Ring

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Display in “Operation” field:

 forwarding: this port is switched on and has a link.
 blocked: this port is blocked and has a link
 disabled: this port is disabled
 not-connected: this port has no link

Figure 6: Ring Redundancy dialog

 In the “Ring Recovery” frame, select 200 ms.

Note: If selecting 200 ms for the ring recovery does not provide the ring
stability necessary to meet the requirements of your network, you select
500 ms.

Note: Settings in the “Ring Recovery” frame are only effective for
devices that you have configured as ring managers.

 Under “Configuration Redundancy Manager”, activate the advanced

mode.

 Activate the ring manager for this device. Do not activate the ring

manager for any other device in the MRP-Ring.

 Leave the VLAN ID as 0 in the VLAN field.
 Switch the operation of the MRP-Ring on.
 Click “Set” to temporarily save the entry in the configuration.

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2.2 Example of a MRP-Ring

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Note: If you want to use the RSTP (see on page 57 “Spanning Tree”)
redundancy protocol in an MRP-Ring, switch on the MRP compatibility on all
devices in the MRP-Ring in the Rapid Spanning Tree:Global dialog as
the RSTP (Spanning-Tree) and ring redundancy affect each other.
If this is not possible, perhaps because individual devices do not support the
MRP compatibility, you deactivate RSTP at the ports connected to the MRP­Ring.

Note: When you are configuring an MRP-Ring using the Command Line
Interface, you define an additional parameter. When configured using CLI, an
MRP-Ring is addressed via its MRP domain ID. The MRP domain ID is a
sequence of 16 number blocks (8-bit values). Use the default domain of 255
255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 for the MRP
domain ID.
This default domain is also used internally for a configuration via the Web­based interface.
Configure all the devices within an MRP-Ring with the same MRP domain ID.

The displays in the “Information” frame mean
– “Redundancy existing”: One of the lines affected by the function may

be interrupted, with the redundant line then taking over the function

of the interrupted line.
– "Configuration failure”: The function is incorrectly configured or the

cable connections at the ring ports are improperly configured (e.g.,

not plugged into the ring ports).
The “VLAN” frame enables you to assign the MRP-Ring to a VLAN:
 If VLANs are configured, you make the following selections in the

"VLAN" frame:

– VLAN ID 0, if the MRP-Ring configuration is not to be assigned to a VLAN, as in

this example.
Select VLAN ID 1 and VLAN membership U (Untagged) in the static VLAN table
for the ring ports.

– A VLAN ID > 0, if the MRP-Ring configuration is to be assigned to this VLAN.

For all devices in this MRP-Ring, enter this VLAN ID in the MRP-Ring
configuration, and then choose this VLAN ID and the VLAN membership Tagged
(T) in the static VLAN table for all ring ports in this MRP-Ring.

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2.2 Example of a MRP-Ring

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enable Switch to the privileged EXEC mode.
configure Switch to the Configuration mode.

mrp new-domain
default-domain

Creates a new MRP-Ring with the default domain
ID

255.255.255.255.255.255.255.255.255.255.255.

255.255.255.255.255.

MRP domain created:
Domain ID:

255.255.255.255.255.255.255.255.255.255.255.255.255.255.255.255
(Default MRP domain)

mrp current-domain
port primary 1/1

Define port 1 in module 1 as ring port 1 (primary).

Primary Port set to 1/1

mrp current-domain
port secondary 1/2

Define port 2 in module 1 as ring port 2
(secondary)

Secondary Port set to 1/2

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2.2 Example of a MRP-Ring

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 Now you connect the line to the ring. To do this, you connect the 2 devices

to the ends of the line using their ring ports.

mrp current-domain mode
manager

Define this device as the ring manager.

Mode of Switch set to manager
mrp current-domain recovery-

delay 200ms

Define 200ms as the value for the “Ring
Recovery”.

Recovery delay set to 200ms

mrp current-domain advanced­mode enable

Activate the “MRP Advanced Mode”.

Advanced Mode (react on link change) set to Enabled

mrp current-domain
operation enable

Activate the MRP-Ring.

Operation set to Enabled
exit Go back one level.
show mrp Show the current parameters of the MRP-Ring

(abbreviated display).

Domain ID:

255.255.255.255.255.255.255.255.255.255.255.255.255.255.255.255
(Default MRP domain)

Configuration Settings:

Advanced Mode (react on link change).... Enabled

Manager Priority........................ 32768

Mode of Switch (administrative setting). Manager
Mode of Switch (real operating state)... Manager

Domain Name............................. <empty>

Recovery delay.......................... 200ms

Port Number, Primary.................... 1/1, State: Not Connected

Port Number, Secondary.................. 1/2, State: Not Connected

VLAN ID................................. 0 (No VLAN)

Operation............................... Enabled

Multiple Rings

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3 Multiple Rings

The device allows you to set up multiple rings with different redundancy
protocols:

 You have the option of coupling to MRP-Rings other ring structures that

work with RSTP (see on page 87 “Combining RSTP and MRP”).

Multiple Rings

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Ring/Network Coupling

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4 Ring/Network Coupling

Ring/Network Coupling allows the redundant coupling of redundant rings and
network segments. Ring/Network Coupling connects 2 rings/network
segments via 2 separate paths.

The ring/network coupling supports the coupling of a ring (HIPER-Ring, Fast
HIPER-Ring or MRP) to a second ring (also HIPER-Ring, Fast HIPER-Ring
or MRP) or to a network segment of any structure, when all the devices in the
coupled network are Hirschmann devices.

The ring/network coupling supports the following devices:

 RS2-./.
 RS2-16M
 RS20, RS30, RS40
 OCTOPUS
 MICE (from rel. 3.0)
 PowerMICE
 MS20, MS30
 RSR20, RSR30
 MACH 100
 MACH 1000
 MACH 1040
 MACH 3000 (from Rel. 3.3),
 MACH 4000

Ring/Network Coupling

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4.1 Variants of the ring/network
coupling

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4.1 Variants of the ring/network
coupling

The redundant coupling is effected by the one-Switch coupling of two ports
of one device in the first ring/network segment to one port each of two
devices in the second ring/network segment (see fig. 8). One of the two
connections – the redundant one – is blocked for normal data traffic in normal
operation.
If the main line no longer functions, the device opens the redundant line
immediately. If the main line functions again, the redundant line is again
blocked for normal data traffic and the main line is used again.
The ring coupling detects and handles an error within 500 ms (typically
150 ms).

The redundant coupling is effected by the two-switch coupling of one port
each from two devices in the first ring/network segment to one port each of
two devices in the second ring/network segment (see fig. 14).
The device in the redundant line and the device in the main line use control
packets to inform each other about their operating states, via the Ethernet or
the control line.
If the main line no longer functions, the redundant device (slave) opens the
redundant line immediately. As soon as the main line is working again, the
device in the main line informs the redundant device of this. The redundant
line is again blocked for normal data traffic and the main line is used again.
The ring coupling detects and handles an error within 500 ms (typically
150 ms).

The type of coupling configuration is primarily determined by the topological
conditions and the desired level of availability (see table 5).