Sometimes, when we start the database, it will fail returning a double fault error:
"No segment started for content: XXX"
Double fault can happen for different reasons; normally we need to check the gpstart logs/pg_logs for details. Sometimes, we can find the messages below in the gpstart log:
Failed segment starts, from mirroring connection between primary and mirror
This message means that the double fault possibly happens because of a connect failure between the primary and mirror of segments during the sync process.
Please note the suggested solution here is just for the message in gpstart log "Failed segment starts, from mirroring connection between primary and mirror," as a double fault can be caused due to various different reasons.
In this example, before checking the pg_logs, we can firstly check if there are any unreachable servers (SSH issue or servers in hardware replacement) where the failed segments reside on; If there is, we need to make the servers connectable first and try gpstart again. If gpstart still fails or all the servers can be reachable, we need to check further in the master/segment logs.