before failing back to primary firewall make sure both units see each other.
show failover | i host
this above command will tell you if the both units can see each other. in case if the command tell you
the "Other host primary - Failed" in that case you need to figure out what causing this issue.
other command which can help you is
show failover state
this command will tell us if the issue was occured due to any Comm Failure. If this is the case you better check the back to back cable/if the swiches are setup in between make sure the cables are connected or the check on the swtiches the primary interfaces and the secondary interface mac address are learned.
you can check the command
show failover history
this command will tell you the break down of the event the occured during this time when the HA unit failed from parimary to secodnadry.
In order to fail back the firewall you need to ssh or console or if on ASDM to fail it back.
here is the method from SSH.
prior to failing back make sure both HA are in good health and see each other with any issue. for example they should be looking like this.
show failover | i host
This host: Primary - Standby
Other host: Secondary - Active
you connect to ssh on the standby firewall and give command
failover active
or you can connected to standby fireall (which is active as active firewall)
you can give command on this firewall
no failover active
this will force the firewall to fall back to primary unite and make it active.
please do not forget to rate.
