Issue Error 502 when trying to log in

[hobaitsolutions]

Server operating system version

Ubuntu 22.04 x86_64

Plesk version and microupdate number

Plesk Obsidian 18.0.50.2

If I try to login, I end up with error 502.

Repair page says sw-engine.service is not running, but I'm unable to start it.

journalctl -xeu sw-engine.service gives following output

░ Subject: Automatic restarting of a unit has been scheduled
░░ Defined-By: systemd
░░ Support: Enterprise open source support | Ubuntu
░░
░░ Automatic restarting of the unit sw-engine.service has been scheduled, as the result for
░░ the configured Restart= setting for the unit.
Feb 23 10:40:33 __server_name__ systemd[1]: Stopped Startup script for Panel sw-engine.
░░ Subject: A stop job for unit sw-engine.service has finished
░░ Defined-By: systemd
░░ Support: Enterprise open source support | Ubuntu
░░
░░ A stop job for unit sw-engine.service has finished.
░░
░░ The job identifier is 1236542 and the job result is done.
Feb 23 10:40:33 __server_name__ systemd[1]: Starting Startup script for Panel sw-engine...
░░ Subject: A start job for unit sw-engine.service has begun execution
░░ Defined-By: systemd
░░ Support: Enterprise open source support | Ubuntu
░░
░░ A start job for unit sw-engine.service has begun execution.
░░
░░ The job identifier is 1236542.
Feb 23 10:40:33 __server_name__ systemd[1]: sw-engine.service: Main process exited, code=exited, status=219/CGROUP
░░ Subject: Unit process exited
░░ Defined-By: systemd
░░ Support: Enterprise open source support | Ubuntu
░░
░░ An ExecStart= process belonging to unit sw-engine.service has exited.
░░
░░ The process' exit code is 'exited' and its exit status is 219.
Feb 23 10:40:33 __server_name__ systemd[1]: sw-engine.service: Failed with result 'exit-code'.
░░ Subject: Unit failed
░░ Defined-By: systemd
░░ Support: Enterprise open source support | Ubuntu
░░
░░ The unit sw-engine.service has entered the 'failed' state with result 'exit-code'.
Feb 23 10:40:33 __server_name__ systemd[1]: Failed to start Startup script for Panel sw-engine.
░░ Subject: A start job for unit sw-engine.service has failed
░░ Defined-By: systemd
░░ Support: Enterprise open source support | Ubuntu
░░
░░ A start job for unit sw-engine.service has finished with a failure.
░░
░░ The job identifier is 1236542 and the job result is failed.

systemctl status sw-engine.service

● sw-engine.service - Startup script for Panel sw-engine
Loaded: loaded (/lib/systemd/system/sw-engine.service; enabled; vendor preset: enabled)
Drop-In: /usr/lib/systemd/system/sw-engine.service.d
└─respawn.conf
Active: activating (auto-restart) (Result: exit-code) since Thu 2023-02-23 10:42:21 CET; 2s ago
Process: 437592 ExecStart=/usr/sbin/sw-engine-fpm --fpm-config /etc/sw-engine/sw-engine-fpm.conf -c /usr/local/psa/admin/conf/php.ini --nodaemonize --pid /run/sw-engine.pid (code=exited, status=219/CGROUP)
Process: 437593 ExecStopPost=/usr/bin/find /run/lock/lmlib/ -mindepth 1 -delete (code=exited, status=219/CGROUP)
Main PID: 437592 (code=exited, status=219/CGROUP)
Tasks: 1 (limit: 165)
Memory: 100.0M
CGroup: /system.slice/sw-engine.service

Feb 23 10:42:21 h3002040.stratoserver.net systemd[1]: sw-engine.service: Failed with result 'exit-code'.
Feb 23 10:42:21 h3002040.stratoserver.net systemd[1]: Failed to start Startup script for Panel sw-engine.

I'm unable to locate the problem, any hints?

 

[hobaitsolutions]

No problems wirth free disk space

root@h3002040:~# df -h
Dateisystem Größe Benutzt Verf. Verw% Eingehängt auf
/dev/ploop43450p1 1000G 41G 910G 5% /
none 4,0M 0 4,0M 0% /sys/fs/cgroup
tmpfs 16G 0 16G 0% /dev/shm
tmpfs 6,5G 224K 6,4G 1% /run
tmpfs 5,0M 20K 5,0M 1% /run/lock
tmpfs 1,0M 0 1,0M 0% /run/credentials/systemd-sysusers.service
none 16G 0 16G 0% /run/shm

 

[Peter Debik]

Do you see any details in /var/log/sw-cp-server/sw-engine.log?

 

[hobaitsolutions]

Contents of /var/log/sw-cp-server/sw-engine.log

[22-Feb-2023 03:45:45] NOTICE: [pool plesk] child 302534 exited with code 0 after 31.038933 seconds from start
[22-Feb-2023 03:45:45] NOTICE: [pool plesk] child 303647 started
[22-Feb-2023 03:45:46] NOTICE: [pool plesk] child 302537 exited with code 0 after 31.031859 seconds from start
[22-Feb-2023 03:45:46] NOTICE: [pool plesk] child 303686 started

for about 100k of lines until it says:

[22-Feb-2023 03:45:48] NOTICE: Terminating ...
[22-Feb-2023 03:45:48] NOTICE: exiting, bye-bye!

 

[Peter Debik]

I think before "Terminating" there must be an additional entry that is not the same than the entries before. Normally there is never a situation where the service just exits without reason. Anyway, please try this solution:

Please edit /etc/sw-engine/pool.d/plesk.conf and remove the comment tags from

;pm.min_spare_servers = 2
;pm.max_spare_servers = 8

so that this reads

pm.min_spare_servers = 2
pm.max_spare_servers = 8

Then please try to start sw-engine again. Does this fix the issue?

 

[hobaitsolutions]

I think before "Terminating" there must be an additional entry that is not the same than the entries before. Normally there is never a situation where the service just exits without reason. Anyway, please try this solution:

Please edit /etc/sw-engine/pool.d/plesk.conf and remove the comment tags from

;pm.min_spare_servers = 2
;pm.max_spare_servers = 8

so that this reads

pm.min_spare_servers = 2
pm.max_spare_servers = 8

Then please try to start sw-engine again. Does this fix the issue?

Thank you, but this did not fix it. The service is running again after uninstalling nginx and a complete reboot. Not sure what fixed or caused it, but for now I'm not going to install nginx again.