On 04/26/2016 03:33 AM, 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.
I don't think it's possible, though I could be wrong, if separate IPs/ports, chroots and node names are used (just shy of a container ...). However I suspect it would not meet your goal in any case. DB and MQ software generally do NOT have sufficient techniques to deal with a split-brain situation -- either you lose high availability or you corrupt data. Using no-quorum-policy=stop is fine for handling network splits, but it does not help if a node becomes unresponsive. Also note that pacemaker does provide the ability to treat different resources differently with respect to quorum and fencing, without needing to run separate clusters. See the "required" meta-attribute: http://clusterlabs.org/doc/en-US/Pacemaker/1.1-pcs/html-single/Pacemaker_Explained/index.html#_resource_meta_attributes I suspect your motive for this is to be able to run a cluster without fencing. There are certain failure scenarios that simply are not recoverable without fencing, regardless of what the application software can do. There is really only one case in which doing without fencing is reasonable: when you're willing to lose your data and/or have downtime when a situation arises that requires fencing. _______________________________________________ Users mailing list: Users@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