[ClusterLabs] Running several instances of a Corosync/Pacemaker cluster on a node

Bogdan Dobrelya bdobrelia at mirantis.com
Tue Apr 26 12:30:39 UTC 2016


On 04/26/2016 10:49 AM, Robert Dahlem wrote:
> On 26.04.2016 10:33, Bogdan Dobrelya wrote:
> 
>> Is it possible to run several instances of a Corosync/Pacemaker clusters
>> on a node? Can a node be a member of several clusters, so they could put
>> resources there? I'm sure it's doable with separate nodes or containers,
>> but that's not the case.
>>
>> My case is to separate data-critical resources, like storage or VIPs,
>> from the complex resources like DB or MQ clusters.
>>
>> The latter should run with no-quorum-policy=ignore as they know how to
>> deal with network partitions/split-brain, use own techniques to protect
>> data and don't want external fencing from a Pacemaker, which
>> no-quorum-policy/STONITH is.
>>
>> The former must use STONITH (or a stop policy, if it's only a VIP), as
>> they don't know how to deal with split-brain, for example.
> 
> And how would you cope with one of the storage nodes STONITHing one of
> the DB nodes?

For that case, one should use separate clusters and sets of nodes.
My case is like a VIP and a DB resources only. When the VIP has to be
stopped in a minority partition, there is no need for STONITH but the
no-quorum-policy=stop. While the DB resource should not be affected and
keep running at the same node, either in a separate cluster - if that
were possible - or in the same cluster - if quorum policy allowed to
"exclude" resources from the stop lists. Too bad none of two is an option.

> 
> Regards,
> Robert
> 
> _______________________________________________
> Users mailing list: Users at clusterlabs.org
> http://clusterlabs.org/mailman/listinfo/users
> 
> Project Home: http://www.clusterlabs.org
> Getting started: http://www.clusterlabs.org/doc/Cluster_from_Scratch.pdf
> Bugs: http://bugs.clusterlabs.org
> 


-- 
Best regards,
Bogdan Dobrelya,
Irc #bogdando




More information about the Users mailing list