PostgreSQL 12 service failing in Ubuntu 20.04 after a few hours

Hi,

I have set up PostgreSQL according to this link:

https://www.cherryservers.com/blog/how-to-install-and-setup-postgresql-server-on-ubuntu-20-04 <https://www.cherryservers.com/blog/how-to-install-and-setup-postgresql-server-on-ubuntu-20-04>

The issue is that after a few hours of operation, even if I don’t access the database at all, the Postgres process fails:

christan(at)vultr:~$ systemctl status postgresql*
● postgresql.service - PostgreSQL RDBMS
Loaded: loaded (/lib/systemd/system/postgresql.service; disabled; vendor preset: enabled)
Active: active (exited) since Sat 2022-12-31 19:56:56 UTC; 24h ago
Process: 3330722 ExecStart=/bin/true (code=exited, status=0/SUCCESS)
Main PID: 3330722 (code=exited, status=0/SUCCESS)

● postgresql(at)12-main(dot)service - PostgreSQL Cluster 12-main
Loaded: loaded (/lib/systemd/system/postgresql(at)(dot)service; enabled-runtime; vendor preset: enabled)
Active: failed (Result: exit-code) since Sat 2022-12-31 21:33:52 UTC; 23h ago
Process: 3330697 ExecStart=/usr/bin/pg_ctlcluster --skip-systemctl-redirect 12-main start (code=exited, status=0/SUCCESS)
Process: 3341739 ExecStop=/usr/bin/pg_ctlcluster --skip-systemctl-redirect -m fast 12-main stop (code=exited, status=2)
Main PID: 3330702 (code=exited, status=0/SUCCESS)

Moreover, it looks like there is some process stuck into some eternal loop, eating up 4 cores:

christan(at)vultr:~$ ps -ef | grep postgres
postgres 3342383 1 0 2022 ? 00:00:00 FzXlkULu
postgres 3344758 1 99 2022 ? 3-14:39:11 OElid7Dp
postgres 3419125 1 18 13:57 ? 01:17:03 tracepath
christan 3463982 3462489 0 20:44 pts/0 00:00:00 grep --color=auto postgres

christan(at)vultr:~$ top -p 3344758
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
3344758 postgres 20 0 2443428 2.3g 4 S 282.3 29.5 5201:46 OElid7Dp

Doing just systemctl postgresql doesn’t restart the process, I have to manually kill all the above processes then do systemctl restart.

Lastly, in the journalctl I see the following logs:

Dec 31 21:33:35 vultr.guest sudo[3340093]: pam_unix(sudo:auth): conversation failed
Dec 31 21:33:35 vultr.guest sudo[3340093]: pam_unix(sudo:auth): auth could not identify password for [postgres]
Dec 31 21:33:35 vultr.guest sudo[3340093]: postgres : user NOT in sudoers ; TTY=unknown ; PWD=/var/lib/postgresql/12/main ; USER=root ; COMMAND=/usr/sbin/sysctl kernel.nmi_watchdog=0
Dec 31 21:33:52 vultr.guest crontab[3341582]: (postgres) LIST (postgres)
Dec 31 21:33:52 vultr.guest crontab[3341584]: (postgres) REPLACE (postgres)
Dec 31 21:33:52 vultr.guest crontab[3341585]: (postgres) LIST (postgres)
Dec 31 21:33:52 vultr.guest crontab[3341588]: (postgres) LIST (postgres)

What am I missing here, maybe I have to make sure that postgres user has sudo rights?

Regards,
Antonis