[DRBD-user] DRBD fencing prevents resource promotion in active/passive cluster

Auer, Jens jens.auer at cgi.com
Tue Sep 20 14:25:55 CEST 2016

Note: "permalinks" may not be as permanent as we would like,
direct links of old sources may well be a few messages off.


Hi,

> Don't disable fencing!

> You need to configure and test stonith in pacemaker. Once that's
> working, then you set DRBD's fencing to 'resource-and-stonith;' and
> configure the 'crm-{un,}fence-handler.sh' un/fence handlers.

> With this, if a node fails (and no, redundant network links is not
> enough, nodes can die in many ways), then drbd will block when the peer
> is lost, call the fence handler and wait for pacemaker to report back
> that the fence action was completed. This way, you will never get a
> split-brain and you will get reliable recovery.

While we will configure fencing finally (and I know that nodes can fail in many ways), it should not be influence the test I am doing because the nodes are not on any unknown state. I have three independant network connections, one for DRBD, one for corosync heartbeats and one for data. In the test, I stop the cluster node manually with 'pcs cluster stop'. I don't think this should trigger STONITH or fencing, but the DRBD fails to get promoted permanently.

Cheers,
  Jens



More information about the drbd-user mailing list