Configuration Synchronization Mechanism; Master Election; Irf Multi-Active Detection; Multi-Active Handling Procedure - HP 6125G Configuration Manual

Configuration synchronization mechanism

IRF uses a strict running-configuration synchronization mechanism so all chassis in an IRF fabric can work
as a single node, and after the master fails, other members can operate normally.
In an IRF fabric, all chassis get and run the running configuration of the master. Any configuration you
have made is propagated to all members.
When you execute the save [ safely ] [ backup | main ] [ force ] command or the save file-url all
command, the system saves the running configuration, as follows:
If the configuration auto-update function (the slave auto-update config command) is enabled, saves
•
the configuration as the startup configuration on all member switches for the next startup.
• If the configuration auto-update function is disabled, saves the configuration as the startup
configuration on the master for the next startup.
By default, configuration auto-update is enabled.
For more information about configuration management, see Fundamentals Configuration Guide.

Master election

Master election is held each time the IRF fabric topology changes, for example, when the IRF fabric is
established, a new member device is plugged in, the master device fails or is removed, the IRF fabric
splits, or IRF fabrics merge.
Master election uses the following rules in descending order:
Current master, even if a new member has higher priority.
1.
When an IRF fabric is being formed, all member switches consider themselves as the master, and
this rule is skipped
Member with higher priority.
2.
Member with the longest system uptime.
3.
Member with the lowest bridge MAC address.
4.
The IRF fabric is formed on election of the master.
During an IRF merge, the switches of the IRF fabric that fails the master election must reboot to re-join the
IRF fabric that wins the election.
After a master election, all subordinate switches initialize and reboot with the configuration on the master.
Their original configuration, even if has been saved, does not take effect.

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, 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.

Multi-active handling procedure

The multi-active handling procedure includes detection, collision handling and failure recovery.
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