![PostgreSQLデータベースサーバーを起動できません。 ——突然[閉じる]](https://linux33.com/image/99087/PostgreSQL%E3%83%87%E3%83%BC%E3%82%BF%E3%83%99%E3%83%BC%E3%82%B9%E3%82%B5%E3%83%BC%E3%83%90%E3%83%BC%E3%82%92%E8%B5%B7%E5%8B%95%E3%81%A7%E3%81%8D%E3%81%BE%E3%81%9B%E3%82%93%E3%80%82%20%E2%80%94%E2%80%94%E7%AA%81%E7%84%B6%5B%E9%96%89%E3%81%98%E3%82%8B%5D.png)
突然postgresqlがクラッシュしました。
$ sudo systemctl status postgresql
● postgresql.service - PostgreSQL database server
Loaded: loaded (/usr/lib/systemd/system/postgresql.service; disabled; vendor preset: disabled)
Active: failed (Result: exit-code) since Sat 2016-11-19 11:09:41 ICT; 8s ago
Process: 20873 ExecStartPre=/usr/bin/postgresql-check-db-dir ${PGROOT}/data (code=exited, status=1/FAILURE)
Nov 19 11:09:40 my_notebook systemd[1]: Starting PostgreSQL database server...
Nov 19 11:09:41 my_notebook systemd[1]: postgresql.service: Control process exited, code=exited status=1
Nov 19 11:09:41 my_notebook systemd[1]: Failed to start PostgreSQL database server.
Nov 19 11:09:41 my_notebook systemd[1]: postgresql.service: Unit entered failed state.
Nov 19 11:09:41 my_notebook systemd[1]: postgresql.service: Failed with result 'exit-code'.
なぜですか？