Plesk repair kit access via http://example.com:8443/repair returns 500 Internal Server Error

Symptoms

• Plesk repair kit via https://example.com:8443/repair shows the following error in the web browser:

  Server Error
  500 external Server Error
  The server encountered an internal error or misconfiguration and was unable to complete your request. Please contact the server administrator to inform of the time the error occurred and of anything you might have done that may have caused the error. More information about this error may be available in the server error log.
  Repair Kit is unavailable. To restore it, log in to the server via SSH, run the command ‘systemctl restart plesk – repaird’, and then refresh this page.

Cause

Plesk repair kit service is inactive:

# systemctl status plesk-repaird
plesk-repaird.service – Repair CP Service
Loaded: loaded (/lib/systemd/system/plesk-repaird.service; disabled; vendor preset: enabled)
Active: inactive (dead) since Sat 2020-10-10 11:04:40 PDT; 10s ago

Resolution

1. Connect to the server via SSH

2. Start the Plesk repair kit service:

   # systemctl start plesk-repaird