On 06/11/13 20:44, Jason Harley wrote:
Hello — I have a four node Corosync (2.3.0-1ubuntu4) cluster configured and happy. However, I’d like to be able to allow the cluster to degrade to a single node in an (extreme) failure state — but still require (at least) two nodes to establish the cluster. Using qdisc is not an option in my environment, so I’m curious if I can achieve this using new features in ‘Needle’ like ‘last_man_standing’ and ‘auto_tie_breaker’. This is the ‘quorum’ block from my corosync.conf:quorum { provider: corosync_votequorum expected_votes: 4 last_man_standing: 1 last_man_standing_window: 10000 auto_tie_breaker: 1 }Is this as simple as telling votequorum that I have a two node cluster (‘two_node: 1’) and enabling ‘allow_downscale’?
What you have should be fine with the addition of "wait_for_all: 1". You probably don't auto_tie_breaker unless there is a likelihood of a 2+2 split on the network.
"two_node" means you have exactly 2 nodes in the cluster (not ever more) so isn't relevant and allow_downscale is solving a different problem than you have.
With last_man_standing the cluster will survive being degraded to 1 node provided there is not a large outage and more than 2 nodes fail at a time.
the man page votequorum.5 has some good examples Chrissie _______________________________________________ discuss mailing list discuss@xxxxxxxxxxxx http://lists.corosync.org/mailman/listinfo/discuss
