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Fallback leader observation mechanism was using a non-quorum read that can see a stale value of multisite status. For purposes of rewinding stadbys this is fine, but if timing was wrong it caused the main HA loop to observe the stale value and promote. Fix this by only running the leader observation fallback while the node is not a leader. If the node is leader the regular heartbeat will take care of updating the view. Observing a stale value during startup is not a problem because promoting to local leader will force a write to global DCS via resolve_leader().
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Fallback leader observation mechanism was using a non-quorum read that can see a stale value of multisite status. For purposes of rewinding stadbys this is fine, but if timing was wrong it caused the main HA loop to observe the stale value and promote.
Fix this by only running the leader observation fallback while the node is not a leader. If the node is leader the regular heartbeat will take care of updating the view.
Observing a stale value during startup is not a problem because promoting to local leader will force a write to global DCS via resolve_leader().