[Pacemaker] Adding Cluster Nodes in Pacemaker "Configuration Explained"

[Andrew Beekhof]

On Thu, Nov 5, 2009 at 4:25 PM, Colin <colin.hch at gmail.com> wrote:
> On Wed, Oct 21, 2009 at 2:57 PM, Andrew Beekhof <andrew at beekhof.net> wrote:
>> On Wed, Oct 21, 2009 at 1:48 PM, Colin <colin.hch at gmail.com> wrote:
>>> Let's see whether I can summarise correctly:
>>
>> basically all correct
>>
>>> For Pacemaker + CoroSync/OpenAIS, the Pacemaker attribute
>>> "expected-quorum-votes" tells the cluster how many votes it needs for
>>> quorum. (What happens when the option is not set?)
>>
>> The cluster sets it for you based on how many nodes it can see.
>
> Something strange is going on here:
>
> - The cluster updates expected-quorum-votes even when I set it
> manually; this seems to happen whenever a node joins or leavs the
> cluster.
>
> - A cluster with four expected-quorum-votes, and three of four nodes
> online, still has quorum; is this a bug??? Or is expected-quorum-votes
> not the number of nodes required in a partition to have quorum?

no, its the total number of nodes seen by the cluster.
the cluster wont allow you to set this to a value less than the number
of nodes it knows about

>
> (I had configured expected-quorum-votes to three for a four-node
> cluster, but it was somehow automatically changed to four, yet the
> three nodes are still having quorum.)
>
> What am I missing?
>
> Thanks, Colin
>
>
> PS: This is with the latest Pacemaker 1.0.6 Debian Lenny packages.
>
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