$ tree -L 2 . ├── 12 │   └── data ├── 9.4 │   └── data ├── data ├── pg_upgrade_internal.log ├── pg_upgrade_server.log └── pg_upgrade_utility.log $ docker run --rm -v `pwd`/:/var/lib/postgresql tianon/postgres-upgrade:9.4-to-12 Performing Consistency Checks ----------------------------- Checking cluster versions ok The source cluster was not shut down cleanly. Failure, exiting