Standby LB becomes Active during HA software update
Normally a software update within the same major release and especially just a Hotfix update is a very easy and less critical task without any downtime. We are using the following steps:
- relicense the Standby device
- install the new software and/or hotfix into different partition
- activate that partition
- verify if everything is loaded correctly
- perform a manual failover
- perform a UAT
- if everything is working correctly, perform all above six steps on the second device
What we noticed is, that sometimes the Standby device will become Active after rebooting into the new installed partition. This might cause unexpected impact/downtime, if something is not loaded correctly with the new software/hotfix. We are not using "Redundancy State Preference". I would expect, that if I reboot a Standby device, that it will always come up as Standby.
I know that if both devices of a cluster will be Active (e.g. due to heartbeat interruption) and they see each other again, that they might end up in a different Active-Standby allocation than before the interruption. If I'm not mistaken this will be calculated based on the mgmt IP or mgmt MAC-address, right? But what's the reason for switching Active-Standby role during activation of a new installed partition? How can this be prevented?
Thank you!
Ciao Stefan :)