Describes the events which occur when a CPM fails over in a VRRP configuration
Below are presented events which occur when a CPM fails over in a system configured for VRRP operation.
Example configuration for below scenario is: Chassis A - Two CPMs with CPM redundancy enabled and the CPMs are synchronized. Chassis B - One or two CPMs.
Scenario assumes that there is no CPM role change on Chassis B.
The CPM fail-over process in a VRRP configuration is as follows:
The backup VRRP chassis (Chassis B) notices through VRRP messages that the primary CPM on the VRRP Master chassis (Chassis A) is not available while the secondary CPM on Chassis A starts all services to become primary CPM.
Chassis B (backup VRRP) becomes Master VRRP.
The secondary CPM in chassis A finishes starting all services, becomes primary CPM and starts to take part in VRRP.
If VRRP preemption has been configured, VRRP fail-back to the new Primary CPM in Chassis A occurs. If VRRP preemption has not been configured, Chassis B remains the VRRP Master.