> On 9 Sep 2015, at 12:13 am, Ken Gaillot <[email protected]> wrote: > > On 09/07/2015 07:48 AM, Jorge Fábregas wrote: >> On 09/07/2015 03:27 AM, Digimer wrote: >>> And this is why I am nervous; It is always ideal to have a primary fence >>> method that has a method of confirming the 'off' state. IPMI fencing can >>> do this, as can hypervisor-based fence methods like fence_virsh and >>> fence_xvm. >> >> Hi Digimer, >> >> Yes, I thought that confirmation was kind of sacred but now I know it's >> not always possible. >> >>> I would use IPMI (iLO, DRAC, etc) as the primary fence method and >>> something else as a secondary, backup method. You can use SBD + watchdog >>> as the backup method, or as I do, a pair of switched PDUs (I find APC >>> brand to be very fast in fencing). >> >> This sounds great. Is there a way to specify a primary & secondary >> fencing device? I haven't seen a way to specify such hierarchy in >> pacemaker. > > Good news/bad news: > > Yes, pacemaker supports complex hierarchies of multiple fencing devices, > which it calls "fencing topology". There is a small example at > http://clusterlabs.org/doc/en-US/Pacemaker/1.1-pcs/html-single/Pacemaker_Explained/index.html#_advanced_stonith_configurations > > Unfortunately, sbd is not supported in fencing topologies.
Another way to look at it, is that sbd is only supported in fencing topologies - just not explicit ones. Self-termination is always the least best option, so we’ll only use it if all other options (including topologies) are exhausted. But we’ll do so automatically. > Pacemaker > hooks into sbd via dedicated internal logic, not a conventional fence > agent, so it's treated differently. You might want to open an RFE bug > either upstream or with your OS vendor if you want to put it on the > radar, but sbd isn't entirely under Pacemaker's control, so I'm not sure > how feasible it would be. > > _______________________________________________ > Users mailing list: [email protected] > 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 _______________________________________________ Users mailing list: [email protected] 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
