>>> Shermal Fernando <sherma...@millenniumit.com> schrieb am 08.09.2016 um >>> 06:41 in Nachricht <8ce6e8d87f896546b9c65ed80d30a4336578c...@lg-spmb-mbx02.lseg.stockex.local>: > The whole cluster will fail if the DC (crm daemon) is frozen due to CPU > starvation or hanging while trying to perform a IO operation. > Please share some thoughts on this issue.
What is "the whole cluster will fail"? If the DC times out, some recovery will take place. > > Regards, > Shermal Fernando > > > > > > > > -----Original Message----- > From: Klaus Wenninger [mailto:kwenn...@redhat.com] > Sent: Monday, September 05, 2016 6:42 PM > To: users@clusterlabs.org; develop...@clusterlabs.org > Subject: Re: [ClusterLabs] When the DC crmd is frozen, cluster decisions are > delayed infinitely > > On 09/03/2016 08:42 PM, Shermal Fernando wrote: >> >> Hi, >> >> >> >> Currently our system have 99.96% uptime. But our goal is to increase >> it beyond 99.999%. Now we are studying the >> reliability/performance/features of pacemaker to replace the existing >> clustering solution. >> >> >> >> While testing pacemaker, I have encountered a problem. If the DC (crm >> daemon) is frozen by sending the SIGSTOP signal, crmds in other >> machines never start election to elect a new DC. Therefore fail-overs, >> resource restartings and other cluster decisions will be delayed until >> the DC is unfrozen. >> >> Is this the default behavior of pacemaker or is it due to a >> misconfiguration? Is there any way to avoid this single point of failure? >> >> >> >> For the testing, we use Pacemaker 1.1.12 with Corosync 2.3.3 in SLES >> 12 SP1 operation system. >> > > Guess I can reproduce that with pacemaker 1.1.15 & corosync 2.3.6. > I'm having sbd with pacemaker-watcher running as well on the nodes. > As the node-health is not updated and the cib can be read sbd is happy - as > to > be expected. > Maybe we could at least add something into sbd-pacemaker-watcher to detect > the > issue ... thinking ... > > Regards, > Klaus > >> >> >> >> >> Regards, >> >> Shermal Fernando >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> This e-mail transmission (inclusive of any attachments) is strictly >> confidential and intended solely for the ordinary user of the e-mail >> address to which it was addressed. It may contain legally privileged >> and/or CONFIDENTIAL information. The unauthorized use, disclosure, >> distribution printing and/or copying of this e-mail or any information >> it contains is prohibited and could, in certain circumstances, >> constitute an offence. If you have received this e-mail in error or >> are not an intended recipient please inform the sender of the email >> and MillenniumIT immediately by return e-mail or telephone (+94-11) >> 2416000. We advise that in keeping with good computing practice, the >> recipient of this e-mail should ensure that it is virus free. We do >> not accept responsibility for any virus that may be transferred by way >> of this e-mail. E-mail may be susceptible to data corruption, >> interception and unauthorized amendment, and we do not accept >> liability for any such corruption, interception or amendment or any >> consequences thereof. >> >> www.millenniumit.com <http://www.millenniumit.com> >> >> >> >> _______________________________________________ >> Users mailing list: Users@clusterlabs.org >> 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: Users@clusterlabs.org > 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: Users@clusterlabs.org > 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: Users@clusterlabs.org 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