I’d like to start on a fresh rancher stack due to too much testing on my current environment. However I’ve one host (and their containers) that I can’t interrupt because the services on it are in production.
So my goal is to create a new rancher-server from scratch and I wanna know how to unlink my critical host from the current rancher-server and link it to the new one ?
Two important points:
my old and new rancher will use custom address space (10.42/16 is already use
the containers on my critical host have been create using the stack feature of rancher
You can destroy the agent container, rm -rf /var/lib/rancher/state, and register it to the new server. The containers will continue to run, but Stack/Service definitions are in the database so they will just show up as standalone containers. I would add that host first, as bad things™ will probably happen if an IP is duplicated on import.
But really if they’re that critical you should probably have a tested way to re-create them from scratch/backup… what happens if that host lights on fire right now?
Thanks for your feedback. In fact my host (where the containers live) don’t gonna move. Only rancher-server will change. I notice your approach and if I’m right the only think I’ll lost is the service/stack definition. I suppose there are no way to create a newstack (in the new rancher-server installation) and import the orphelin containers ?
Your second proposal to recreate container from schratch could be okay, all there containers use convoy (with devicemapper), so I’ll try this approach maybe.
and reinject the old containers in the new ones.