Forum Discussion
Stefan_Klotz
Cumulonimbus
CumulonimbusStandby 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 :)
Let me answer this by myself again.
The above mentioned steps are still fine, but what we did for a while now is setting the standby-LB into offline mode before booting into the new partition. With this the LB will also come up again in offline mode. When you then release offline mode it will always become correctly the standby-LB.
Hope this might help someone out there.
Ciao Stefan :)
There is one warning with your method. It wont work on Viprions or vCMP Guests managed by Self IP.
https://support.f5.com/csp/article/K15122
- On VIPRION systems, the system terminates connections to self IP addresses and does not allow new connections.
- Note: When you enable Force Offline, the Traffic Management Microkernel (TMM) interfaces remain configured until the unit is restarted. If the system is restarted while Force Offline is enabled, the system marks all TMM interfaces as Uninitialized or Missing. This behavior is by design; the system does not attempt to initialize and bring up TMM interfaces while the system is in the offline state.
- For vCMP guests and hypervisors on VIPRION platforms, the system terminates connections to self IP addresses, and does not allow new connections.
So if you are not using vCMP Guests and Viprion Platforms managed by Self IP you are doing it in a supported method. If you are using Viprion or vCMP managed by self IP Forced offline will prevent you from managing the devices outside the Management IP.
Hope this helps avoid any mishaps.
-Mike M.
- Stefan_Klotz
Let me answer this by myself again.
The above mentioned steps are still fine, but what we did for a while now is setting the standby-LB into offline mode before booting into the new partition. With this the LB will also come up again in offline mode. When you then release offline mode it will always become correctly the standby-LB.
Hope this might help someone out there.
Ciao Stefan :)
- Stefan_Klotz
Hi Mike,
thanks for the hint! I wasn't aware of that as we are not using/working with Viprions or vCMPs.
I think most of the others out there as well, but nethertheless good to know.
Ciao Stefan :)
