We had a situation where we applied HF4 cumulative patch on standby and at some point both of out ltms went active/active and we had a outage.
In order to prevent this to happen again we are thinking of isolating ltm12-2 from the network and apply the patch and disable asm. SO we are thinking of
disabling all the interfaces on LTM12-2 including HA interface .
Here is my steps and concerns
In step 5 and 6
once I reboot and
1) Currently LTM12-2 is active. So we will failover to standby
(2) On ltm12-2 change the redundancy state preference to standby.
(3) Disable network interfaces
(4) Reactivate license on LTM12-2 to disable ASM
(6) Enable HA interface and than other network interfaces on LTM12-2