[ClusterLabs] Fencing on 2-node cluster

[Casey & Gina]

Does this mean that fencing can't actually work in a 2-node cluster??  Or is it just that the delay needs set differently on one of the hosts and it will start working?

> On 2018-06-20, at 3:50 PM, Digimer <lists at alteeve.ca> wrote:
> 
> 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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