For the setup of a new IRF fabric, the subordinate devices must reboot to complete the setup after the
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
Multi-active handling procedure
The multi-active handling procedure includes detection, collision handling, and failure recovery.
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 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:
Compares the number of members in each fabric.
Sets the fabric that has the most members to the Detect state, and all other fabrics to the Recovery
Compares the member IDs of their masters if all IRF fabrics have the same number of members.
Sets the IRF fabric that has the lowest numbered master to the Detect state, and all other fabrics to
the Recovery (disabled) state.
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:
Sets the IRF fabric that has the lowest numbered master to the Detect state.
Sets all other fabrics to the Recovery state.
Takes the same action on the network ports in Recovery-state fabrics as LACP MAD.
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.