[ClusterLabs] Strange behavior of Resource stickiness

[Andrei Borzenkov]

On Tue, May 28, 2024 at 11:39 AM Александр Руденко <a.rudikk at gmail.com> wrote:
>
> Hi!
>
> I can't understand this strange behavior, help me please.
>
> I have 3 nodes in my cluster, 4 vCPU/8GB RAM each. And about 70 groups, 2 resources in each group. First one resource is our custom resource which configures Linux VRF and second one is systemd unit. Everything works fine.
>
> We have next defaults:
> pcs resource defaults
> Meta Attrs: rsc_defaults-meta_attributes
>   resource-stickiness=100
>
> When I shutdown pacemaker service on NODE1, all the resources move to NODE2 and NODE3, it's okay. But when I start pacemaker service on NODE1, 3 of 70 groups move back to NODE1.
> But I expect that no one resource will be moved back to NODE1.
>
> I tried to set resource-stickiness=100 exactly for these 3 groups, but it didn't help.
>
> pcs resource config fsmt-41CC55C0
>  Group: fsmt-41CC55C0
>   Meta Attrs: resource-stickiness=100
> ...
>
> Why are these 3 resource groups moving back?
>

Because NODE1 score is higher than NODE2 score + 100. E.g. NODE1 score
may be infinity.