zero downtime upgrades - SOP?

[आलोक कुमार]

Fellow keycloak users,

Are there any steps to take for a zero downtime upgrade of keycloak? I just went thru the upgrading guide at https://www.keycloak.org/docs/latest/upgrading/index.html and it does involve backing up and restoring data (not as a safety measure, but because the upgrade will lose all the config previously done)

This would mean that while the upgrade is in progress, nobody can login to the application.

That's not ideal, however small that upgrade window may be.

I did find documentation on setting up an HA cluster on k8s in two different ways - however that's only when the application is already running, not during the upgrade process. Upgrade does involve database backup and restore, so it doesn't appear that a standard rolling deployment will work (ie one pod running the old version while the other pods get upgraded)

Maybe I'm wrong because it's difficult to believe that all keycloak users just live with downtime when upgrade is in progress, or that downtime during upgrade is very miniscule, looking forward to being enlightened by you.

If it matters our keycloak deployment is on a kubernetes cluster.

thanks in advance,

Alok