HP FlexFabric 12900 series User manual

HP FlexFabric 12900 Switch Series
IRF
Configuration Guide
Part number: 5998-7267a
Software version: R103x
Document version: 6W100-20160728

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i
Contents
Setting up an IRF fabric ··············································································································································· 3
Overview············································································································································································3
Network topologies ··························································································································································4
Basic concepts···································································································································································4
Operating mode·······················································································································································5
IRF member roles ······················································································································································5
IRF member ID···························································································································································5
MPU roles··································································································································································5
IRF port ······································································································································································5
IRF physical interface ···············································································································································6
MAD ··········································································································································································6
IRF domain ID ···························································································································································6
IRF split ······································································································································································7
IRF merge ··································································································································································7
Member priority························································································································································8
Configuration synchronization ········································································································································8
Master election··································································································································································8
Multi-active handling procedure······································································································································9
Detection ···································································································································································9
Collision handling ····················································································································································9
Failure recovery ························································································································································9
MAD mechanisms ·························································································································································· 10
LACP MAD ····························································································································································· 10
BFD MAD ······························································································································································· 11
General restrictions and configuration guidelines······································································································ 12
Hardware compatibility········································································································································ 12
Software requirements ·········································································································································· 12
IRF size ··································································································································································· 13
MPU requirements ················································································································································· 13
IRF physical interface requirements ····················································································································· 13
Connecting IRF ports ············································································································································· 14
IRF link redundancy··············································································································································· 14
Multichassis link aggregation ······························································································································ 14
Feature compatibility and configuration restrictions·························································································· 14
Configuration backup ··········································································································································· 14
Setup and configuration task list ·································································································································· 15
Planning the IRF fabric setup········································································································································· 15
Preconfiguring IRF member devices in standalone mode ·························································································· 16
Assigning a member ID to each IRF member device························································································· 16
Specifying a priority for each member device··································································································· 16
Binding physical interfaces to IRF ports ·············································································································· 16
Saving configuration to the next-startup configuration file ························································································ 17
Connecting IRF physical interfaces······························································································································· 18
Setting the operating mode to IRF mode ····················································································································· 18
Accessing the IRF fabric ················································································································································ 19
Configuring IRF member devices in IRF mode ············································································································ 19
Assigning an IRF domain ID to the IRF fabric····································································································· 20
Changing the member ID of a device················································································································· 20
Changing the priority of a member device ········································································································ 20

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Adding physical interfaces to an IRF port··········································································································· 21
Enabling IRF auto-merge······································································································································· 23
Configuring a member device description ········································································································· 23
Isolating an unused IRF member ID ····················································································································· 23
Configuring IRF link load sharing mode ············································································································· 24
Configuring IRF bridge MAC persistence··········································································································· 25
Setting the IRF link down report delay ················································································································ 26
Configuring MAD·················································································································································· 26
Displaying and maintaining an IRF fabric··················································································································· 31
Configuration examples ················································································································································ 32
LACP MAD-enabled IRF configuration example for a two-chassis IRF fabric·················································· 32
BFD MAD-enabled IRF configuration example for a two-chassis IRF fabric···················································· 35
Configuration example for restoring standalone mode ···················································································· 38
Support and other resources ·····································································································································41
Contacting HP ································································································································································ 41
Subscription service ·············································································································································· 41
Related information························································································································································ 41
Documents······························································································································································ 41
Websites································································································································································· 41
Conventions ···································································································································································· 42
Index ···········································································································································································44

3
Setting up an IRF fabric
Overview
HP Intelligent Resilient Framework (IRF) technology virtualizes multiple physical devices at the same layer
into one virtual fabric to provide data center class availability and scalability. IRF virtualization
technology offers processing power, interaction, unified management, and uninterrupted maintenance
of multiple devices.
Figure 1 shows an IRF fabric that has two devices, which appear as a single node to the upper-layer and
lower-layer devices.
Figure 1 IRF application scenario
IRF provides the following benefits:
•Simplified topology and easy management—An IRF fabric appears as one node and is accessible
at a single IP address on the network. You can use this IP address to log in at any member device
to manage all the members of the IRF fabric. In addition, you do not need to run the spanning tree
feature among the IRF members.
•1:N redundancy—In an IRF fabric, one member works as the master to manage and control the
entire IRF fabric. All the other members process services while backing up the master. When the
master fails, all the other member devices elect a new master from among them to take over without
interrupting services.
•IRF link aggregation—You can assign several physical links between neighboring members to their
IRF ports to create a load-balanced aggregate IRF connection with redundancy.
•Multichassis link aggregation—You can use the Ethernet link aggregation feature to aggregate the
physical links between the IRF fabric and its upstream or downstream devices across the IRF
members.

4
•Network scalability and resiliency—Processing capacity of an IRF fabric equals the total
processing capacities of all the members. You can increase ports, network bandwidth, and
processing capacity of an IRF fabric simply by adding member devices without changing the
network topology.
Network topologies
The HP 12900 IRF fabric only supports the daisy-chain topology. For information about connecting IRF
member devices, see "Connecting IRF physical interfaces."
Basic concepts
This section uses Figure 2 to describe the basic concepts that you might encounter when you work with
IRF.
Figure 2 Two-chassis IRF fabric implementation schematic diagram
In this figure, Device A and Device B form a two-chassis IRF fabric. The fabric has four MPUs (one active
and three standbys), and two times the number of interface cards that a single device provides. The IRF
fabric manages the physical and software resources of Device A and Device B in a centralized manner.
IRF link
An IRF
fabric is
formed.
Master
(Member ID=1)
Subordinate
(Member ID=2)
Active MPU
Device A
(Member ID=1) Device B
(Member ID=2)
IRF physical
interfaces IRF physical
interfaces
IRF-port 2 IRF-port 1
Network
interfaces
Network
interfaces
IRF
Standby MPU
Active MPU
Standby MPU
IRF’s master MPU
IRF’s standby MPU
IRF’s standby MPU
IRF’s standby MPU

5
Operating mode
The device operates in one of the following modes:
•Standalone mode—The device cannot form an IRF fabric with other devices.
•IRF mode—The device can form an IRF fabric with other devices.
IRF member roles
IRF uses two member roles: master and standby (called subordinate throughout the documentation).
When devices form an IRF fabric, they elect a master to manage and control the IRF fabric, and all the
other devices back up the master. When the master device fails, the other devices automatically elect a
new master. For more information about master election, see "Master election."
IRF member ID
An IRF fabric uses member IDs to uniquely identify and manage its members. This member ID information
is included as the first part of interface numbers and file paths to uniquely identify interfaces and files in
an IRF fabric. Two devices cannot form an IRF fabric if they have the same IRF member ID. A device
cannot join an IRF fabric if its member ID has been used in the fabric.
For example, after you assign a device with a member ID of 2 to an IRF fabric, the name of interface
Ten-GigabitEthernet 3/0/1 changes to Ten-GigabitEthernet 2/3/0/1. The file path changes from
slot16#flash:/test.cfg to chassis2#slot16#flash:/test.cfg.
MPU roles
Each IRF member device has one or two MPUs. The following are MPU roles:
Role Description
Master MPU Active MPU of the master device. It is also called the global active MPU. You
configure and manage the entire IRF fabric at the CLI of the global active MPU.
Active MPU
Active MPU on each member device. An active MPU performs the following
tasks:
•Manages the local device, including synchronizing configuration with the
local standby MPU, processing protocol packets, and creating and
maintaining route entries.
•Processes IRF-related events, such as master election and topology collection.
Standby MPU
For the master MPU, all other MPUs are standby MPUs, including active MPUs
on subordinate devices.
If a member device has two MPUs, the MPU backing up the local active MPU is
the local standby MPU from the perspective of the member device.
IRF port
An IRF port is a logical interface that connects IRF member devices. Every IRF-capable device has two IRF
ports.

6
In standalone mode, the IRF ports are named IRF-port 1 and IRF-port 2.
In IRF mode, the IRF ports are named IRF-port n/1 and IRF-port n/2, where nis the member ID of the
device. The two IRF ports are referred to as IRF-port 1 and IRF-port 2 in this book.
To use an IRF port, you must bind a minimum of one physical interface to it. The physical interfaces
assigned to an IRF port automatically form an aggregate IRF link. An IRF port goes down only if all its IRF
physical interfaces are down.
IRF physical interface
IRF physical interfaces connect IRF member devices and must be bound to an IRF port. They forward
traffic between member devices, including IRF protocol packets and data packets that must travel across
IRF member devices.
For more information about physical interfaces that can be used for IRF links, see "IRF physical interface
requirements."
MAD
An IRF link failure causes an IRF fabric to split in two IRF fabrics operating with the same Layer 3 settings,
including the same IP address. To avoid IP address collision and network problems, IRF uses multi-active
detection (MAD) mechanisms to detect the presence of multiple identical IRF fabrics, handle collisions,
and recover from faults.
IRF domain ID
One IRF fabric forms one IRF domain. IRF uses IRF domain IDs to uniquely identify IRF fabrics and prevent
IRF fabrics from interfering with one another.
As shown in Figure 3, IRF fabric 1 contains Device A and Device B, and IRF fabric 2 contains Device C
and Device D. Both fabrics use the LACP aggregate links between them for MAD. When a member
device receives an extended LACPDU for MAD, it checks the domain ID to see whether the packet is from
the local IRF fabric. Then, the device can handle the packet correctly.

7
Figure 3 A network that contains two IRF domains
IRF split
IRF split occurs when an IRF fabric breaks up into multiple IRF fabrics because of IRF link failures, as
shown in Figure 4. The split IRF fabrics operate with the same IP address and cause routing and
forwarding problems on the network. To quickly detect a multi-active collision, configure a minimum of
one MAD mechanism (see "Configuring MAD").
Figure 4 IRF split
IRF merge
IRF merge occurs when two split IRF fabrics reunite or when two independent IRF fabrics are united, as
shown in Figure 5.
Device A Device B
IRF fabric 1
(domain 10)
IRF link
Core network
IRF fabric 2
(domain 20)
IRF link
Device C Device D
Access network

8
Figure 5 IRF merge
Member priority
Member priority determines the possibility of a member device to be elected the master. A member with
higher priority is more likely to be elected the master.
Configuration synchronization
IRF uses a strict running-configuration synchronization mechanism. In an IRF fabric, all devices obtain
and run the running configuration of the master. Any configuration change is automatically propagated
from the master to the remaining devices. The configuration files of these devices are retained, but the
files do not take effect. The devices use their own startup configuration files only after they are removed
from the IRF fabric.
For more information about configuration management, see Fundamentals Configuration Guide.
Master election
Master election occurs each time the IRF fabric topology changes in the following situations:
•The IRF fabric is established.
•The master device fails or is removed.
•The IRF fabric splits.
•Independent IRF fabrics merge.
NOTE:
Master election does not occur when two split IRF fabrics merge.
Master election selects a master in descending order:
1. Current master, even if a new member has higher priority.
When an IRF fabric is being formed, all member devices consider themselves as the master. This
rule is skipped.
2. Member with higher priority.
3. Member with the longest system uptime.
Two members are considered to start up at the same time if their startup time difference is equal to
or less than 10 minutes. For these members, the next tiebreaker applies.
4. Member with the lowest member ID.

9
For the setup of a new IRF fabric, the subordinate devices must reboot to complete the setup after the
master election.
For an IRF merge, devices must reboot if they are in the IRF fabric that fails the master election. The reboot
can be performed automatically or manually, depending on the IRF auto-merge configuration (see
"Enabling IRF auto-merge").
Multi-active handling procedure
The multi-active handling procedure includes detection, collision handling, and failure recovery.
Detection
MAD identifies each IRF fabric with a domain ID and an active ID (the member ID of the master). If
multiple active IDs are detected in a domain, MAD determines that an IRF collision or split has occurred.
For more information about the MAD mechanisms and their application scenarios, see "MAD
mechanisms."
Collision handling
MAD mechanisms remove multi-active collisions by setting one IRF fabric to the Detect state and other IRF
fabrics to the Recovery state. The Detect-state IRF fabric is active. The Recovery-state IRF fabric is inactive.
Only members in the Detect-state fabric can continue to forward traffic.
LACP MAD uses the following process to handle a multi-active collision:
1. Compares the number of members in each fabric.
2. Sets the fabric that has the most members to the Detect state, and all other fabrics to the Recovery
state.
3. Compares the member IDs of their masters if all IRF fabrics have the same number of members.
4. Sets the IRF fabric that has the lowest numbered master to the Detect state, and all other fabrics to
the Recovery (disabled) state.
5. Shuts down all physical network ports in the Recovery-state fabrics except for the following ports:
{IRF physical interfaces.
{Ports you have specified with the mad exclude interface command.
In contrast, BFD MAD does not compare the number of members in fabrics. BFD MAD uses the following
process to handle a multi-active collision:
1. Sets the IRF fabric that has the lowest numbered master to the Detect state.
2. Sets all other fabrics to the Recovery state.
3. Takes the same action on the network ports in Recovery-state fabrics as LACP MAD.
Failure recovery
To merge two split IRF fabrics, first repair the failed IRF link and remove the IRF link failure.
•If the IRF fabric in Recovery state fails before the failure is recovered, repair the failed IRF fabric and
the failed IRF link.

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•If the active IRF fabric fails before the failure is recovered, enable the inactive IRF fabric to take over
the active IRF fabric. Then, recover the MAD failure.
MAD mechanisms
IRF provides MAD mechanisms by extending LACP and BFD.
IMPORTANT:
Do not configure BFD MAD with LACP MAD, because they handle collisions differently.
Table 1 compares the MAD mechanisms and their application scenarios.
Table 1 Comparison of MAD mechanisms
MAD
mechanism Advantages Disadvantages Application scenario
LACP MAD
•Detection speed is fast.
•Does not require
MAD-dedicated physical
links or Layer 3 interfaces.
Requires an intermediate
device that supports
extended LACP for MAD.
Link aggregation is used
between the IRF fabric
and its upstream or
downstream device.
For information about
LACP, see Layer 2—LAN
Switching Configuration
Guide.
BFD MAD
•Detection speed is fast.
•No intermediate device is
required.
•Intermediate device, if used,
can come from any vendor.
•Requires MAD dedicated
physical links and Layer 3
interfaces, which cannot
be used for transmitting
user traffic.
•If no intermediate device
is used, the IRF members
must be fully meshed.
•If an intermediate device
is used, every IRF
member must connect to
the intermediate device.
•No special
requirements for
network scenarios.
•If no intermediate
device is used, this
mechanism is only
suitable for IRF fabrics
that have a small
number of members
that are
geographically close
to one another.
For information about
BFD, see High
Availability
Configuration Guide.
LACP MAD
As shown in Figure 6, LACP MAD has the following requirements:
•Every IRF member must have a link with an intermediate device.
•All the links form a dynamic link aggregation group.
•The intermediate device must be an HP device that supports extended LACP for MAD.

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The IRF member devices send extended LACPDUs that convey a domain ID and an active ID. The
intermediate device transparently forwards the extended LACPDUs received from one member device to
all the other member devices.
•If the domain IDs and active IDs sent by all the member devices are the same, the IRF fabric is
integrated.
•If the extended LACPDUs convey the same domain ID but different active IDs, a split has occurred.
LACP MAD handles this situation as described in "Collision handling."
Figure 6 LACP MAD scenario
BFD MAD
BFD MAD can work with or without intermediate devices. Figure 7 shows a typical BFD MAD application
scenario.
To use BFD MAD:
•Set up dedicated BFD MAD link between each pair of IRF members or between each IRF member
and the intermediate device. Do not use the BFD MAD links for any other purpose.
•Assign the ports connected by BFD MAD links to the same VLAN.
•Create a VLAN interface for the VLAN, and assign a MAD IP address to each member on the VLAN
interface.
NOTE:
The MAD IP addresses identify the member devices and must belong to the same subnet.
Intermediate device
Master Subordinate
IRF fabric
Internet
Customer
premise
network
IRF link
Common traffic path
LACP MAD traffic path
LACP-enabled dynamic
link aggregation
LACP-enabled dynamic
link aggregation

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With BFD MAD, the master tries to establish BFD sessions with other member devices by using its MAD
IP address as the source IP address.
•If the IRF fabric is integrated, only the MAD IP address of the master is effective. The master cannot
establish a BFD session with any other member. If you execute the display bfd session command,
the state of the BFD sessions is Down.
•When the IRF fabric splits, the IP addresses of the masters in the split IRF fabrics take effect. The
masters can establish a BFD session. If you use the display bfd session command, the state of the
BFD session between the two devices is Up.
Figure 7 BFD MAD scenario
General restrictions and configuration guidelines
For a successful IRF setup, follow the restrictions and guidelines in this section and the setup procedure
in "Setup and configuration task list."
Hardware compatibility
An HP 12900 switch can form an IRF fabric with devices of the same model.
Software requirements
All IRF member devices must run the same software image version.

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IRF size
An HP 12900 IRF fabric can contain a maximum of two chassis.
MPU requirements
Every IRF member must have a minimum of one MPU.
IRF physical interface requirements
Use the following ports as IRF physical interfaces:
•10 -G E p ort s.
•40-GE ports.
•100 -GE por ts.
Selecting transceiver modules
When you select transceiver modules and cables, follow these restrictions and guidelines:
•Use transceiver modules and fibers to connect IRF physical interfaces for a long-distance
connection.
•Use SFP+ or QSFP+ DAC cables to connect IRF physical interfaces for a short-distance connection.
•The transceiver modules at the two ends of an IRF link must be the same type. For more information
about transceiver modules, see the device installation guide.
Grouped port restrictions
The port grouping rules are as follows:
•The 10-GE ports are grouped by port number in order, starting from 1. Each group contains four
ports.
•The breakout interfaces of a 40-GE or 100-GE port belong to one port group.
When you use the ports in a group for IRF links and specify the binding mode as enhanced, follow these
restrictions and guidelines:
•You must use all or none of the ports in the group for IRF links. The ports can be bound to different
IRF ports.
•Before you bind one of the ports to an IRF port or remove it from the IRF port, you must shut down
all the ports in the group. If any of the ports are in up state, the bind or remove action will fail.
•Bring up the ports after you complete the operations.
When you use a 40-GE or 100-GE port as an IRF physical interface, no grouping restrictions exist.
On an LSX1QGS16EA card (JG625A), no ports can be used for IRF links if the 40-GE ports indexed by
1 to 8 are all split to 10-GE breakout interfaces.
Port split (the using tengige command) and combination (the using fortygige command) require a card
reboot. To avoid topology change, HP recommends that you complete these operations before you add
the device to an IRF fabric. When you perform these operations in an IRF fabric, make sure you
understand the impact on the IRF fabric topology. For more information about 40-GE or 100-GE port split
and combination operations, see Layer 2—LAN Switching Configuration Guide.

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Connecting IRF ports
When you connect two neighboring IRF members, follow these restrictions and guidelines:
•You must connect the physical interfaces of IRF-port 1 on one member device to the physical
interfaces of IRF-port 2 on the other device.
•Do not connect physical interfaces of both IRF ports on one member device to the physical
interfaces of both IRF ports on the other device.
IRF link redundancy
When you configure an IRF fabric, follow these link redundancy restrictions and guidelines:
•For link redundancy and load sharing, bind a maximum of eight physical interfaces to one IRF port.
•As a best practice to prevent a card removal from causing an IRF split, bind physical interfaces on
multiple cards to one IRF port.
Multichassis link aggregation
For high availability, connect a downstream device to each IRF member device, and assign the links to
one link aggregation group.
Feature compatibility and configuration restrictions
ECMP
All member devices in the IRF fabric must have the same setting for the maximum number of ECMP routes.
For more information about configuring ECMP, see Layer 3—IP Routing Configuration Guide.
MDC
If the IRF fabric splits, do not change the MDC settings on any IRF member devices before they reunite.
Before you use the undo mdc command to delete an MDC, remove IRF port bindings for the physical
interfaces on the MDC and save the configuration. To identify physical interfaces bound to IRF ports, use
the display irf link command.
System operating mode
All member devices in the IRF fabric must work in the same system operating mode (set by using the
system-working-mode command). For more information about the system operating mode, see
Fundamentals Configuration Guide.
TRILL
If TRILL is used, configure the irf mac-address persistent always command to retain the IRF bridge MAC
address permanently. The persistence setting ensures that other devices in the TRILL network can maintain
correct network topology after the bridge MAC address owner leaves the IRF fabric.
Configuration backup
HP recommends that you back up the next-startup configuration file on a device before adding the device
to an IRF fabric as a subordinate.

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A subordinate device's next-startup configuration file might be overwritten if the master and the
subordinate use the same file name for their next-startup configuration files. You can use the backup file
to restore the original configuration after removing the subordinate from the IRF fabric.
Setup and configuration task list
HP recommends the following IRF fabric setup and configuration procedure:
Tasks at a glance Remarks
1. (Required.) Planning the IRF fabric setup N/A
2. (Required.) Preconfiguring IRF member devices in standalone mode:
{Assigning a member ID to each IRF member device
{Specifying a priority for each member device
{Binding physical interfaces to IRF ports
Perform this task on each member
device before IRF mode is enabled.
3. (Required.) Saving configuration to the next-startup configuration file
N/A
4. (Required.) Connecting IRF physical interfaces Make sure that they are
interoperable.
5. (Required.) Setting the operating mode to IRF mode N/A
6. (Required.) Accessing the IRF fabric N/A
7. (Optional.) Configuring IRF member devices in IRF mode:
{Assigning an IRF domain ID to the IRF fabric
{Changing the member ID of a device
{Changing the priority of a member device
{Adding physical interfaces to an IRF port
{Enabling IRF auto-merge
{Configuring a member device description
{Isolating an unused IRF member ID
{Configuring IRF link load sharing mode
{Configuring IRF bridge MAC persistence
{Setting the IRF link down report delay
{Configuring MAD
CAUTION:
Changing member IDs in an IRF
fabric can void member ID-related
configuration and cause
unexpected problems. Make sure
you understand the impact on your
live network before you change
member IDs.
Adding physical interfaces to an IRF
port is required if you did not
configure IRF port bindings in
standalone mode.
Planning the IRF fabric setup
Consider the following items when you plan an IRF fabric:
•Hardware compatibility and restrictions.
•IRF fabric size.
•Master device.
•IRF physical interfaces.
•Member ID and priority assignment scheme.
•Fabric topology and cabling scheme.
For more information about hardware and cabling, see the installation guide for the device.

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Preconfiguring IRF member devices in standalone
mode
Perform the preconfiguration tasks on every IRF member device. These settings take effect on each
member device after their operating mode changes to IRF.
Assigning a member ID to each IRF member device
A device by default operates in standalone mode without an IRF member ID. You must assign it a unique
IRF member ID before changing its operating mode to IRF.
The member ID assigned to the device is saved in both active and standby MPUs. The standby MPU
might store a different member ID than the active MPU after an MPU replacement. For consistency, the
system updates the member ID in the active MPU automatically to the standby MPU when the difference
is detected.
To set a member ID for the device in standalone mode:
Step Command Remarks
1. (Optional.) Verify the
member ID assignment
status.
display irf configuration
Check the MemberID field. If the
device does not have an IRF
member ID, the field displays
two hyphens (--).
2. Enter system view. system-view N/A
3. Assign an IRF member ID to
the device. irf member member-id By default, the device does not
have an IRF member ID.
Specifying a priority for each member device
IRF member priority represents the possibility for a device to be elected the master in an IRF fabric. The
higher the priority, the higher the possibility.
To specify a priority for the device in standalone mode:
Step Command Remarks
1. Enter system view. system-view N/A
2. Specify a priority for the
device. irf priority priority The default IRF member priority
is 1.
Binding physical interfaces to IRF ports
To establish an IRF connection between two devices, you must bind a minimum of one physical interface
to IRF-port 1 on one device and to IRF-port 2 on the other. For link redundancy and load sharing, bind
multiple physical interfaces to one IRF port.

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Make sure the IRF physical interfaces are operating as Layer 2 interfaces. Layer 3 interfaces cannot be
bound to IRF ports. To configure a physical interface as a Layer 2 or Layer 3 interface, use the port
link-mode { bridge | route } command. For more information about this command, see Layer 2—LAN
Switching Configuration Guide.
In standalone mode, IRF port binding operations do not affect the current configuration of the interface.
However, when the operating mode changes to IRF mode, the default configuration is restored on the IRF
physical interface. You can only execute the description, flow-interval, and shutdown commands on the
physical interface. For more information about these commands, see Layer 2—LAN Switching Command
Reference.
When you specify a binding mode for an IRF physical interface, follow these restrictions and guidelines:
•The binding mode of all IRF physical interfaces bound to an IRF port must be the same (enhanced
or extended).
•The two ends of an IRF link must use the same binding mode.
•To use EVB, TRILL, MPLS L2VPN, or VPLS in the IRF fabric, you must configure the IRF physical
interfaces to operate in enhanced mode.
•To connect member devices through optical transmission devices, you must configure the IRF
physical interfaces to operate in extended mode. Only ports on EB and EC cards can operate in
extended mode.
To bind physical interfaces to IRF ports:
Step Command Remarks
1. Enter system view. system-view N/A
2. Enter IRF port view. irf-port port-number N/A
3. Bind a physical interface to
the IRF port.
port group interface interface-type
interface-number [ mode { enhanced |
extended } ]
By default, no physical interfaces
are bound to any IRF port.
Repeat this step to assign
additional physical interfaces to
the IRF port.
Each IRF port can have a
maximum of eight physical
interfaces.
If you do not specify a binding
mode, the enhanced mode
applies.
Saving configuration to the next-startup
configuration file
Save the running configuration before converting to the IRF mode. The mode change requires a reboot,
which causes all unsaved settings to be lost.
Perform the following task in any view:

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Task Command
Save the running configuration to
the next-startup configuration file. save [ safely ] [ backup | main ] [ force ]
Connecting IRF physical interfaces
When you connect two neighboring IRF members, connect the physical interfaces of IRF-port 1 on one
member to the physical interfaces of IRF-port 2 on the other (see Figure 8).
When you connect fiber ports, connect the transmit port of the transceiver module at one end to the
receive port of the transceiver module at the other end.
IMPORTANT:
You can use optical transmission devices to connect geographically dispersed IRF members. However, you
must disable MAC address learning and checking on the optical transmission devices.
Figure 8 Connecting IRF physical interfaces
Connect the devices into a daisy-chain topology.
Figure 9 IRF daisy-chain topology
Setting the operating mode to IRF mode
By default, the device operates in standalone mode. To assign the device to an IRF fabric, you must
change its operating mode to IRF mode.