[ClusterLabs] Fencing on 2-node cluster

[Digimer]

On 2018-06-20 05:46 PM, Jehan-Guillaume de Rorthais wrote:
> On Wed, 20 Jun 2018 17:24:41 -0400
> Digimer <lists at alteeve.ca> wrote:
> 
>> Make sure quorum is disabled. Quorum doesn't work on 2-node clusters.
> 
> It does with the "two_node" parameter enabled in corosync.conf...as far as I
> understand it anyway...

It doesn't, that option disables quorum in corosync.

Quorum is floor(($nodes / 2) + 1). So in a 3-node, that is 3 -> 1.5 ->
2.5 -> 2 votes needed for quorum. In a 2-node, that is 2 -> 1 -> 2 -> 2
votes needed for quorum, meaning you can't lose a node to operate (which
is kinda not HA :) ).

-- 
Digimer
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