Multi-Active Handling Procedure; Detection; Collision Handling; Failure Recovery - HP FlexFabric 5700 series Configuration Manual

For an IRF merge, devices must reboot if they are in the IRF fabric that fails the master election.

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
mechanisms."

Collision handling

When MAD detects a multi-active collision, it sets all IRF fabrics except one to the Recovery state. The
fabric that is not placed in Recovery state can continue to forward traffic. The Recovery-state IRF fabrics
are inactive and cannot 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 all fabrics to the Recovery state except the one that has the most members.
3. Compares the member IDs of the masters if all IRF fabrics have the same number of members.
4. Sets all fabrics to the Recovery state except the one that has the lowest numbered master.
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, ARP MAD and ND MAD do not compare the number of members in fabrics. These MAD
mechanisms use the following process to hand a multi-active collision:
1. Compare the member IDs of the masters in the IRF fabrics.
2. Set all fabrics to the Recovery state except the one that has the lowest numbered master.
3. Take 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.
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.
7
"MAD