[pve-devel] update to corosync 2.0 in proxmox 4, upgrade without shutdown vms ?

[Dietmar Maurer]

> I'm seeing that you currently looking to upgrade corosync to v2 for jessie.
> 
> AFAIK, corosync v2 it not compatibile with v1,
> So all nodes should be upgraded at the same time.

yes.

> But as we update to jessie too, I wonder how to do it, without reboot all
> hosts at the same time,
> so killing all vms.

I thing an update could work this way:

1.) cman and rgmanager are dead, so first step would be to remove rgmanager.

2.) After that, we can try to (automatically) create a cluster configuration
for the new system:

/etc/corosync/authkey (copy to all nodes)
/etc/pve/corosync.conf

Then update node by node

3.) find another solution for HA

We need to test if that works...