> On Fri, Jul 23, 2021 at 8:55 AM Ulrich Windl < > ulrich.wi...@rz.uni-regensburg.de> wrote: > >> >>> "john tillman" <jo...@panix.com> schrieb am 22.07.2021 um 16:48 in >> Nachricht >> <1175ffcec0033015e13d11d7821d5acb.squir...@mail.panix.com>: >> > There was a lot of discussion on this topic which might have >> overshadowed >> > this question so I will ask it again in case someone missed it. >> > >> > It comes from a post (see below) that we were pointed to here by >> Andrei: >> > >> > Is there something like the described "ping tiebreaker" in the current >> > world of pacemaker/corosync? >> >> Maybe explain how it should work: >> If the two nodes cannot rech each other, but each can reach the ping >> node, >> which node has the quorum then? >> > > Guess both - which is what is played down as 'disadvantage' in the > description > below ;-) > >
It is not perfect, I agree, but it may be better than nothing at all. As for how it worked in my head: I would have used the switch's IP address as the "ping" tie breaker; a common connection point between the two nodes. My assumption is that if there was network loss by Node A then it would lose quorum. In the mean time Node B would still reach the switch, achieve quorum, and start/move resources. Thank you for your responses. Ken G. posted a suggestion of using "corosync-qdevice" on a third node. I'll look into that but I may not be able to install software on a third node. If anyone can think of another path to follow, please let me know. >> >> > >> > Best Regards, >> > âJohn >> > >> >> Interesting read. Thank you for providing it! >> >> >> >> In this follow up post >> >> >> > >> https://techthoughts.typepad.com/managing_computers/2007/10/more >> âaboutâquor.htm >> >> > l >> >> the author mentions the following: >> >> >> >> Ping tiebreaker >> >> >> >> Some HA systems provide a ping tiebreaker. To make this work, you >> pick a >> >> address outside the cluster to ping, and any partition that can ping >> that >> >> address has quorum. The obvious advantage is that it's very simple >> to >> set >> >> up â doesn't require any additional servers or shared disk. The >> >> disadvantage (and it's a big one) is that it's very possible for >> multiple >> >> partitions to think they have quorum. In the case of splitâsite >> (disaster >> >> recovery) type clusters, it's going to happen fairly often. If you >> can >> >> use this method for a single site in conjunction with fencing, then >> it >> >> will likely work out quite well. It's a lot better than no >> tiebreaker, >> or >> >> one that always says "you have quorum". Having said that, it's >> >> significantly inferior to a _______________________________________________ Manage your subscription: https://lists.clusterlabs.org/mailman/listinfo/users ClusterLabs home: https://www.clusterlabs.org/
