Hi, On Thu, Jan 24, 2008 at 04:02:55PM -0600, [EMAIL PROTECTED] wrote: > Quoting Dejan Muhamedagic <[EMAIL PROTECTED]>: > >> Hi, >> >> On Fri, Jan 25, 2008 at 09:03:01AM +1300, Steve Wray wrote: >>> Forgive top posting but I just noted this in some documentation: >>> >>> "Provided both HA nodes can communicate with each other, ipfail can >>> reliably detect when one of their network links has become unusable, and >>> compensate." >>> >>> In the example which I give this is not the case; the loss of >>> connectivity >>> is complete. The nodes cannot communicate with one another. >> >> That's called split brain. Not a very nice thing for clusters. >> Definitely to be avoided. See http://www.linux-ha.org/SplitBrain > > I'm confronted with a similar issue, but for a different reason. The two > nodes in our heartbeat/drbd cluster are located in physically remote data > centers. We have 2 separate GigE interfaces, routed through separate > switches, to maintain heartbeat communication. > > Every few months, our IT department simulates a disaster which would make > our primary data center completely unavailable. They cut both the fiber > links between the centers, so the primary data center has absolutely no > connectivity. This forces all systems to operate from the backup center, > just to be sure we'll be ready if something actually demands it. > > We've never had any problems running out of the backup center, except that > we're guaranteed to have a split-brain when the 2 centers are reconnected. > I would really like to figure out a way to tell the node in the primary > center 'if you can't contact your ping node, don't become primary'.
You can configure constraints to stop resources in case the ping attribute is not greater than zero. Thanks, Dejan > Is this an unreasonable goal? Is there something I could do differently in > this situation? The only other option I can think of is to sit at my desk > in the primary center during the test and manually stop heartbeat just > before the test starts. > > thanks, > alex > _______________________________________________ > Linux-HA mailing list > [email protected] > http://lists.linux-ha.org/mailman/listinfo/linux-ha > See also: http://linux-ha.org/ReportingProblems _______________________________________________ Linux-HA mailing list [email protected] http://lists.linux-ha.org/mailman/listinfo/linux-ha See also: http://linux-ha.org/ReportingProblems
