[INFRA-3005] 2021-06-17 | AKS upgrade (1.18 -> 1.19)

[Damien Duportal]

Hello everybody,

This Thursday, 17th of June 2021, we'll upgrade the AKS cluster from 1.18 to 1.19, starting at 08:00 UTC.

No interruption is expected, except for the non-replicated services such as ldap.jenkins.io, infra.ci.jenkins.io or release.ci.jenkins.io that need to be restarted (in order to be migrated to the new nodes).

You may find the notes about this upgrade at the following location: https://hackmd.io/EDpvZx9ZS2GWgHHqWFRDfQ?view#118x-to-119x . It contains all the links, comment, discussions.

A JIRA issue is also present (https://issues.jenkins.io/browse/INFRA-3005).

Cheers!

Damien Duportal

PS: thanks Gavin and Tim for the comments, tests and feedback that makes us feeling safe about this upgrade