Plesk is not accessible with error 502 and sw-engine fails to start: failed to open error_log (/var/log/sw-cp-server/sw-engine.log): No such file or directory (2)

Symptoms

• Plesk is not accessible:

  502 Bad Gateway

• The service sw-engine is down:

  # systemctl status sw-engine -l
  ..........
  plesk.example.com systemd[1]: Starting Startup script for Panel sw-engine...
  plesk.example.com sw-engine-fpm[17102]: ERROR: failed to open error_log (/var/log/sw-cp-server/sw-engine.log): No such file or directory (2)
  plesk.example.com sw-engine-fpm[17102]: ERROR: failed to post process the configuration
  plesk.example.com sw-engine-fpm[17102]: ERROR: FPM initialization failed
  plesk.example.com systemd[1]: sw-engine.service: main process exited, code=exited, status=78/n/a
  plesk.example.com systemd[1]: sw-engine.service stop-sigterm timed out. Killing.
  plesk.example.com systemd[1]: Failed to start Startup script for Panel sw-engine.
  plesk.example.com systemd[1]: Unit sw-engine.service entered failed state.
  plesk.example.com systemd[1]: sw-engine.service failed.

Cause

The log file /var/log/sw-cp-server/sw-engine.log does not exist on the server.

Resolution

1. Connect to the server using SSH.

2. Re-create the log directory if it does not exist:

   # if [ ! -d "/var/log/sw-cp-server" ]; then mkdir /var/log/sw-cp-server && chmod 750 /var/log/sw-cp-server; fi

3. Re-create the missing log file:

   # touch /var/log/sw-cp-server/sw-engine.log && chmod 600 /var/log/sw-cp-server/sw-engine.log

4. Start sw-engine:

   # service sw-engine start