[ClusterLabs] Antw: [EXT] Inquiry - remote node fencing issue

[Andrei Borzenkov]

On 28.10.2021 20:13, Gerry R Sommerville wrote:
> 
> What we also found to be interesting is that if the cluster is only using a 
> single heartbeat ring, then srv-2 will get fenced instead, and the 

So as already suspected you did not actually isolate the node at all.

> pacemaker-remote connection resources will successfully fail over without any 
> additional fencing to the remote nodes themselves. It seems a little backwards 
> to us since our reasoning for configuring multiple heartbeat rings was to 
> increase the clusters reliability/robustness of the cluster, but it seems to do 
> the opposite when using pacemaker-remote. :(
> 

Remote node is still node. It does not participate in quorum and it does
not perform fencing but otherwise it is part of cluster. If you have
redundant rings you are expected to provide redundant connection to
remote nodes as well to match it.

You do not complain that srv-2 is fenced when its single connection is
down; how does it differ from srv-4 being fenced when its single
connection is down?

> Any suggestions/comments on our configuration / test scenario's are appreciated!

Every HA configuration is as reliable as its weakest link. If you make
half of connections redundant and half of connections not, not redundant
connections will be single point of failure.

Besides, you never actually described what is the problem you are trying
to solve. If you had no active resources on remote node, how does it
matter whether this node was fenced? If you had active resources, those
resources would have failed over to another node.