I think OP is wrong in their hypothesis based on the logs they share and the root cause AWS support provided them.
I think the promotion fails to happen and then an external watchdog notices that it didn’t, and kills everything ASAP as it’s a cluster state mismatch.
The message about the storage subsystem going away is after the other Postgres process was kill -9’d.
I think the promotion fails to happen and then an external watchdog notices that it didn’t, and kills everything ASAP as it’s a cluster state mismatch.
The message about the storage subsystem going away is after the other Postgres process was kill -9’d.