A membership callback can be one of the following events:
- OC_EV_MS_NEW_MEMBERSHIP
- CCM: membership with quorum
- CRM/CIB quorum: true
CRM/CIB actions: update membership instance & contents
- CRM actions: none (we wait for the CRMd on that node to become active before any CRM action is taken)
The TE monitors CIB updates and detects and nodes that unexpectedly left - starting/restarting a transition if required
- OC_EV_MS_MS_INVALID
- CCM: membership without quorum
- CRM/CIB quorum: false
CRM/CIB actions: update membership instance & contents
DC actions: Invoke the PolicyEngine to ensure the "No Quorum Policy" is observed
- OC_EV_MS_NOT_PRIMARY
- CCM: old membership (not valid any longer)
- CRM/CIB quorum: no change
- DC actions: cancel the transition if one is in progress
- OC_EV_MS_PRIMARY_RESTORED This event mean the cluster restores to a stable state that has the same membership as before. It also implies it has the same quorum as before.
- CCM: old membership restored (same membership as before)
- CRM/CIB quorum: no change
- CRM/CIB actions: update membership instance
- DC actions: Start/restart a transition now that everything is now stable (in theory we would have gotten a OC_EV_MS_NOT_PRIMARY before this which would have cancelled the transition)
- OC_EV_MS_EVICTED
- CCM: the client is evicted from ccm.
- CRM/CIB quorum: false
CRM/CIB actions: update membership instance & contents, shut down This should not happen if correct startup/shutdown order is observed.