[ClusterLabs] DRBD not failing over

[Jaap Winius]

Quoting Jaap Winius <jwinius at umrk.nl>:

> Very interesting. I'm already running DRBD 9, so that base has  
> already been covered, but here's some extra information: My test  
> system actually consists of a single 4-node DRBD cluster that spans  
> two data centers, with each data center having a 2-node Pacemaker  
> cluster to fail resources over between the two DRBD nodes in that  
> data center. But, for the purpose of quorum arbitration I guess  
> these extra DRBD nodes don't matter, perhaps because four is not an  
> odd number?

No, four nodes are enough and I eventually figured it out. There was  
an extra firewall port that may have helped (2224), but I suspect that  
the main problem was that I forgot to enable the SELinux boolean for  
DRBD: daemons_enable_cluster_mode=1. Now everything is working  
perfectly.

Thanks,

Jaap