"Unable to acquire lock on file '/tmp/pgbackrest/Repo-backup.lock'
When this happens, take a look inside this file. If there is another pgbackrest process running, the pid will be inside that file. Kill that process before trying to run another backup.
Or don't run pgbackrest when another instance is running. This is what I do:
pgrep -a pgbackrest | grep -q "pgbackrest backup" && { echo "another pgbackrest back is running"; exit 1; }
(There's probably a better way to check that, but this works.)
