fix: fail liveness probe when replication heartbeat is stale#25
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The liveness probe only checked conn.IsClosed(), which reports an explicitly closed connection but not a network-dead one. On a Postgres primary failover, the replication connection to the old primary goes silently dead: the periodic heartbeat fails and flips isAlive to false (so /ready returns 500), but /healthz stayed green and k8s never restarted the pod. The pod then ran indefinitely pointing at the old primary. Include isAlive in the liveness check so a stalled heartbeat fails /healthz, letting Kubernetes restart the pod and reconnect to the new primary through the Service. Signed-off-by: Imtiaz Uddin <imtiaz@appscode.com>
NotTabassum
approved these changes
Jun 17, 2026
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The liveness probe only checked conn.IsClosed(), which reports an explicitly closed connection but not a network-dead one. On a Postgres primary failover, the replication connection to the old primary goes silently dead: the periodic heartbeat fails and flips isAlive to false (so /ready returns 500), but /healthz stayed green and k8s never restarted the pod. The pod then ran indefinitely pointing at the old primary.
Include isAlive in the liveness check so a stalled heartbeat fails /healthz, letting Kubernetes restart the pod and reconnect to the new primary through the Service.