2014-05-27 7:34 GMT+02:00 Andrew Beekhof <and...@beekhof.net>: > > On 27 May 2014, at 3:12 pm, Gao,Yan <y...@suse.com> wrote: > > > On 05/27/14 08:07, Andrew Beekhof wrote: > >> > >> On 26 May 2014, at 10:47 pm, Christian Ciach <derein...@gmail.com> > wrote: > >> > >>> I am sorry to get back to this topic, but I'm genuinely curious: > >>> > >>> Why is "demote" an option for the ticket "loss-policy" for > multi-site-clusters but not for the normal "no-quorum-policy" of local > clusters? This seems like a missing feature to me. > >> > >> Or one feature too many. > >> Perhaps Yan can explain why he wanted demote as an option for the > loss-policy. > > Loss-policy="demote" is a kind of natural default if the "Master" mode > > of a resource requires a ticket like: > > <rsc_ticket rsc="ms1" rsc-role="Master" ticket="ticketA"/> > > > > The idea is for running stateful resource instances across clusters. And > > loss-policy="demote" provides the possibility if there's the need to > > still run the resource in slave mode for any reason when losing the > > ticket, rather than stopping it or fencing the node hosting it. > > I guess the same logic applies to the single cluster use-case too and we > should allow no-quorum-policy=demote. > > Thank you for mentioning this. This was my thought as well.
At the moment we "simulate" this behaviour by using a primitive resource where "started" means "master" and "stopped" means "slave". This way we can use "no-quorum-policy=stop" to actually switch the resource to slave on quorum loss. This seems hacky, so I would appreciate if this could be done in a proper way some time in the future. > One question though... do we still stop non-master/slave resources for > loss-policy=demote? > > > > > Regards, > > Yan > > > >> > >>> > >>> Best regards > >>> Christian > >>> > >>> > >>> 2014-04-07 9:54 GMT+02:00 Christian Ciach <derein...@gmail.com>: > >>> Hello, > >>> > >>> I am using Corosync 2.0 with Pacemaker 1.1 on Ubuntu Server 14.04 > (daily builds until final release). > >>> > >>> My problem is as follows: I have a 2-node (plus a quorum-node) cluster > to manage a multistate-resource. One node should be the master and the > other one the slave. It is absolutely not allowed to have two masters at > the same time. To prevent a split-brain situation, I am also using a third > node as a quorum-only node (set to standby). There is no redundant > connection because the nodes are connected over the internet. > >>> > >>> If one of the two nodes managing the resource becomes disconnected, it > loses quorum. In this case, I want this resource to become a slave, but the > resource should never be stopped completely! This leaves me with a problem: > "no-quorum-policy=stop" will stop the resource, while > "no-quorum-policy=ignore" will keep this resource in a master-state. I > already tried to demote the resource manually inside the monitor-action of > the OCF-agent, but pacemaker will promote the resource immediately again. > >>> > >>> I am aware that I am trying the manage a multi-site-cluster and there > is something like the booth-daemon, which sounds like the solution to my > problem. But unfortunately I need the location-constraints of pacemaker > based on the score of the OCF-agent. As far as I know location-constraints > are not possible when using booth, because the 2-node-cluster is > essentially split into two 1-node-clusters. Is this correct? > >>> > >>> To conclude: Is it possible to demote a resource on quorum loss > instead of stopping it? Is booth an option if I need to manage the location > of the master based on the score returned by the OCF-agent? > >>> > >>> > >>> _______________________________________________ > >>> Pacemaker mailing list: Pacemaker@oss.clusterlabs.org > >>> http://oss.clusterlabs.org/mailman/listinfo/pacemaker > >>> > >>> Project Home: http://www.clusterlabs.org > >>> Getting started: > http://www.clusterlabs.org/doc/Cluster_from_Scratch.pdf > >>> Bugs: http://bugs.clusterlabs.org > >> > > > > -- > > Gao,Yan <y...@suse.com> > > Software Engineer > > China Server Team, SUSE. > > > > _______________________________________________ > > Pacemaker mailing list: Pacemaker@oss.clusterlabs.org > > http://oss.clusterlabs.org/mailman/listinfo/pacemaker > > > > Project Home: http://www.clusterlabs.org > > Getting started: http://www.clusterlabs.org/doc/Cluster_from_Scratch.pdf > > Bugs: http://bugs.clusterlabs.org > > > _______________________________________________ > Pacemaker mailing list: Pacemaker@oss.clusterlabs.org > http://oss.clusterlabs.org/mailman/listinfo/pacemaker > > Project Home: http://www.clusterlabs.org > Getting started: http://www.clusterlabs.org/doc/Cluster_from_Scratch.pdf > Bugs: http://bugs.clusterlabs.org > >
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