[Linux-cluster] 4 node cluster even split

[Patrick Caulfield]

Janne Peltonen wrote:
> Hi!
> 
> I've been wondering...
> 
> If I were to build a 4 node cluster, what would happen (with default
> quorum settings) if I lost two nodes at once (say, by losing one of my
> two blade racks)?  Would the remaining two nodes be able to continue, or
> would they consider quorum dissolved and shut down the remaining
> services? I only have three nodes for testing purposes, so I haven't
> been able to look at this yet.

Under normal circumstances you need (n/2)+1 nodes to keep quorum. So if you lose
two nodes out of four then the services will stop. To prevent this you can use
the qdisk program to keep the cluster quorate in such circumstances.

-- 
Patrick

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