[Pacemaker] Split Site 2-way clusters

[Colin]

Hi All,

we are currently looking at nearly the same issue, in fact I just
wanted to start a similarly titled thread when I stumbled over these
messages…

The setup we are evaluating is actually a 2*N-node-cluster, i.e. two
slightly separated sites with N nodes each. The main difference to an
N-node-cluster is that a failure of one of the two groups of nodes
must be considered a single failure event [against which the cluster
must protect, e.g. loss of power at one site].

As far as I gather from this, and other, mail threads, there is
currently no out-of-the-box quorum-something solution for pacemaker.
Before I start digging deeper [into possible solutions], there's one
question I need to ask:

In a pacemaker + corosync setup, who decides whether a partition has
quorum? I.e, would a quorum-device mechanism need to be integrated
with corosync, or with pacemaker, or with both?

Thanks, Colin