On Sun, 2011-12-04 at 23:47 +0100, Andreas Kurz wrote: > Hello, > > On 12/04/2011 09:29 PM, Muhammad Sharfuddin wrote: > > This cluster reboots(fenced) both nodes, if I disconnects network of any > > nodes(simulating network failure). > > Completely loss of network is indistinguishable for a cluster node to a > dead peer. > > > > > I want that if any node disconnects from network, resources running on > > that node should be moved/migrate > > to the other node(network connected node) > > Use ping RA for connectivity checks and use location constraints to move > resources according to network connectivity (to external ping targets) > so in case of having a ping RA with appropriate location rule, does at least make sure that if any one node lose the network connectivity(i.e both nodes cant see each other, while only one node is disconnected from network), the other healthy node(network connected node) wont reboot ... is it what you said ? > > > > How can I prevent this cluster to reboot(fence) the healthy node(i.e the > > node whose network is up/available/connected). > > Multiple-failure scenarios are challenging and possible solutions for a > cluster are limited. With enough effort by an administrator every > cluster can be "tested to death". > > You can only minimize the possibility of a split-brain: > > * use redundant cluster communication paths (limited to two with corosync) in my test I disconnected every communication path of one node(and both rebooted)
> * at least one communication path is direct connected directly connected communication path and ping RA with location rule.. will prevent the reboot of healthy node(network connected node) > * use a quorum node > i.e I should add another node(quorum node) in this two node cluster. > If you are using a network connected fencing device use this network > also for cluster communication. > > To prevent stonith death matches use power-off as stonith action or/and > don't start cluster services on system startup. > cluster does not start at system startup > Regards, > Andreas > > _______________________________________________ > Linux-HA mailing list > Linux-HA@lists.linux-ha.org > http://lists.linux-ha.org/mailman/listinfo/linux-ha > See also: http://linux-ha.org/ReportingProblems -- Regards, Muhammad Sharfuddin _______________________________________________ Linux-HA mailing list Linux-HA@lists.linux-ha.org http://lists.linux-ha.org/mailman/listinfo/linux-ha See also: http://linux-ha.org/ReportingProblems
