[Pacemaker] Two resource nodes + one quorum node

[Andrew Beekhof]

On 14/06/2013, at 2:14 PM, Nikita Staroverov <nsforth at gmail.com> wrote:

>> Its certainly possible to build a decent 2-node cluster, but there are several non-obvious steps that are required - preventing fencing loops being one. For this reason I cannot recommend them for newcomers, because they are also the most likely group to be unaware of the caveats.
> I think it's not so difficult.

Its not difficult once you understand its necessary.
Its gaining the understanding that is the hurdle.

What you don't know that you don't know can most certainly harm your cluster.
I could not possibly count the number of conversations that started with "why is everything stopped when the other node goes down?" detoured via "why do I need fencing?" and ended with "whats a fencing loop?".

> There are only two fine points, imho.
> First, manual cluster services starting.
> Second, avoiding fence race in split brain situations by adding in fence agent random action timeout which is big enough.
> 
> 
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