Irf Fabric Configuration Task List - H3C S9500E Series Configuration Manual

IRF fabric topology maintenance
As soon as a member switch is down or an IRF link is down, its neighbor switches broadcast the leaving
of the switch to other members. When a member switch receives the leave message, it looks up its IRF
topology database to determine whether the leaving switch is the master. If yes, the member switch starts
a master election and updates its IRF topology database. If the leaving switch is not a master, the member
switch directly updates its IRF topology database.
NOTE:
An IRF port goes down only when all its physical IRF ports are down.
IRF multi-active detection
An IRF link failure causes an IRF fabric to split in two IRF fabrics operating with the same Layer 3
configurations, such as the same IP address. To avoid IP address collisions and network problems, IRF
uses the multi-active detection (MAD) mechanism to detect the presence of multiple identical IRF fabrics
and handle collisions. MAD provides the following functions:
Detection
1.
MAD detects multiple identical active IRF devices with the same global configuration by extending the
Link Aggregation Control Protocol (LACP), the Bidirectional Forwarding Detection (BFD) protocol, or the
Gratuitous Address Resolution (ARP) protocol. For more information, see
Collision handling
2.
If multiple identical active IRF fabrics are detected, only the IRF fabric that has the lowest master ID can
operate in active state and forward traffic normally. MAD sets all other IRF fabrics in recovery state
(disabled) and shuts down all physical ports but the console and physical IRF ports and other ports you
have specified with the mad exclude interface command.
Failure recovery
3.
An IRF link failure triggers IRF fabric partition and causes multi-active collision. In this case, repair the
failed IRF link to make the collided IRF fabrics merge into one and recover the failure. If the IRF fabric in
recovery state fails before the failure is recovered, repair both the failed IRF fabric and the failed IRF link,
and then the collided IRF fabrics can merge into one and the failure is recovered. If the IRF fabric in active
state fails before the failure is recovered, enable the IRF fabric in recovery state at the CLI to make it take
over the active IRF fabric and protect the services from being affected. Then, recover the MAD failure.
NOTE:
For information about LACP, see
High Availability Configuration Guide
BFD, see
Services Configuration Guide

IRF fabric configuration task list

There are two IRF fabric configuration methods, pre-configuration and non pre-configuration. The
pre-configuration method is recommended because only one switch reboot is needed to complete the
configuration.
Layer 2—LAN Switching Configuration Guide
. For information about gratuitous ARP, see
.
8
"Configuring MAD detection."
. For information about
Layer 3—IP