>>> Andrei Borzenkov <arvidj...@gmail.com> schrieb am 28.01.2021 um 18:30 in Nachricht <db12df26-6cc4-bad2-8bf5-8ee3aad87...@gmail.com>: > 27.01.2021 22:03, Ken Gaillot пишет: >> >> With a group, later members depend on earlier members. If an earlier >> member can't run, then no members after it can run. >> >> However we can't make the dependency go in both directions. If an >> earlier member can't run unless a later member is active, and vice >> versa, then how can anything be started? >> >> By default, Pacemaker tries to recover failed resources on the same >> node, up to its migration-threshold (which defaults to a million >> times). Once a group member reaches its migration-threshold, Pacemaker >> will move the entire group to another node if one is available. However >> if no node is available for the failed member, then it will just remain >> stopped (along with any later members in the group), and the earlier >> members will stay active where they are. >> >> I don't think there's any way to prevent earlier members from running >> if a later member has no available node. >> > > All other HA managers I am aware of have collection of resources (often > called "application") as scheduling unit. All resources in one > collection are automatically activated on the same node (they of course > (may) have ordering dependencies). If any required resource in > collection fails, partially active collection is cleaned up, all > resources activated so far are deactivated. This is indeed virtually > impossible to express in pacemaker. The only way I can think of is > artificially restrict management layer to top-level resources, but this > also won't work for stopping group of resources (where "group" is used > generically, not in narrow pacemaker sense) for reasons you explained.
I just wonder: Adding op timeouts to a group? If the groups fails to start or stop within the specific time, consider the whole group as failed... stop a failed start, and fence a failed stop... Regards, Ulrich > > _______________________________________________ > Manage your subscription: > https://lists.clusterlabs.org/mailman/listinfo/users > > ClusterLabs home: https://www.clusterlabs.org/ _______________________________________________ Manage your subscription: https://lists.clusterlabs.org/mailman/listinfo/users ClusterLabs home: https://www.clusterlabs.org/