[ClusterLabs] resource management of standby node

[Andrei Borzenkov]

On Mon, Nov 30, 2020 at 3:11 PM Ulrich Windl
<Ulrich.Windl at rz.uni-regensburg.de> wrote:
>
> Hi!
>
> In SLES15 I'm surprised what a standby node does: My guess was that a standby node would stop all resources and then just "shut up", but it seems it still tried to place resources and calls monitor operations.
>

Standby nodes are ineligible for running resources. It does not stop
pacemaker from trying to place resources somewhere in cluster.

> Like this after a configuration change:
> pacemaker-controld[49413]:  notice: Result of probe operation for prm_test_raid_md1 on h18: not running
>

Probe is not monitor. Normally it happens once when the pacemaker is
started. It should not really be affected by putting node in standby.

> Or this (on the DC node):
> pacemaker-schedulerd[69599]:  notice: Cannot pair prm_test_raid_md1:0 with instance of cln_DLM
>

So? As mentioned, pacemaker still attempts to manage resources, it
just excludes standby nodes from the list of possible candidates. If
all nodes are in standby mode, no resource can run anywhere, but
pacemaker still needs to try placing resources to see it. Maybe you
really want cluster maintenance mode instead.

> Maybe I should have done differently, but after a test setup I noticed that I named by primitives in a non-consistent way, and wanted to mass-rename resources.
> As from the past renaming running resources had issues, I wanted to stop all resources before changing the configuration.
> So I was expecting the cluster to be silent until I put at least one node online again.
>
> Expectation failed. Is there a better way to do it?
>
> Regards,
> Ulrich
>
>
> _______________________________________________
> Manage your subscription:
> https://lists.clusterlabs.org/mailman/listinfo/users
>
> ClusterLabs home: https://www.clusterlabs.org/