On Tue, 2011-11-29 at 21:16 +0100, Tim Serong wrote: > On 11/29/2011 04:28 PM, Muhammad Sharfuddin wrote: > > On Mon, 2011-11-28 at 21:47 +0100, Tim Serong wrote: > >> On 11/28/2011 06:54 PM, Muhammad Sharfuddin wrote: > >>> is it good/required to create order constraint for sbd resource > >>> > >>> I am using following fencing resource: > >>> > >>> primitive sbd_stonith stonith:external/sbd \ > >>> meta target-role="Started" \ > >>> op monitor interval="3000" timeout="120" \ > >>> op start interval="0" timeout="120" \ > >>> op stop interval="0" timeout="120" \ > >>> params > >>> sbd_device="/dev/disk/by-id/scsi-360080e50002377b8000002ff4e4bc873" > >>> > >>> I have following order constraints: > >>> > >>> order resA-before-resB inf: resA resB symmetrical=true > >>> order resB-before-resC inf: resB resC symmetrical=true > >>> > >>> should I also create another constraint for sbd like: > >>> > >>> order sbd_stonith-before-resA inf: sbd_stonith resA symmetrical=true > >>> > >>> please help/suggest. > >> > >> No. The STONITH resource doesn't need to be running in order for your > >> other resources to be operable (hence no need for an order constraint). > >> > >> Regards, > >> > >> Tim > > true, but if there is an order constraint for the STONITH resource, then > > it will at least make it sure that no other resource will be start > > before the STONITH resource. > > > > e.g: > > order sbd_stonith-before-resA inf: sbd_stonith resA symmetrical=true > > > > order resA-before-resB inf: resA resB symmetrical=true > > order resB-before-resC inf: resB resC symmetrical=true > > > > Because I stopped all the resources including STONITH resource(and > > stopping any resource sets the 'target-role="Stopped"'), then started > > all other resources else/except the STONITH resource, so at that time my > > cluster has no fencing resource available. > > So, don't stop the STONITH resource :) > > Side point: if you use "crm configure property stop-all-resources=true", > this will stop all resources *except* for any STONITH resources. The > point being, you do always want them running... > thanks, its a nice tip
> > So in order to protect the cluster I thought that there should(must) be > > an order constraint that specifies that no other resource(s) will be > > start if STONITH resource is stopped/unavailable. > > > > Please suggest/recommend > > You should generally be OK without order constraints on STONITH > resources. I don't recall seeing any other systems where people had > created these constraints. I should also note that if, say, your > STONITH resource is running on node-0 and that node dies, the cluster > will start the STONITH resource on node-1, to kill node-0. It's smart > enough. > yeah I also noticed this, its smart ;) > Worst case, if your STONITH resource is completely broken, and a node > fails and thus can't be killed, the cluster will sit there and log > errors to syslog about its inability to kill the misbehaving node. > > (Question for everyone else: did I miss anything?) > > Regards, > > Tim Thanks everyone for the suggestions and recommendations -- Regards, Muhammad Sharfuddin Technical Manager Cell: +(92) 333-2144823 | UAN: +(92-21) 111-111-142 ext: 113 | Web: http://www.nds.com.pk _______________________________________________ Linux-HA mailing list [email protected] http://lists.linux-ha.org/mailman/listinfo/linux-ha See also: http://linux-ha.org/ReportingProblems
