Server restart command is giving 500 OOPS error

  1. Describe the issue briefly
    When is write the command sudo <file_name> restart for the server to restart it gives 500 OOPS error
  2. How much time have you spent debugging this issue?
    (Please spend at least 15 minutes to resolve the issue on your own before posting a new topic here)
    1.5 hours
  3. What is your hypothesis?

Try To look on forum you will find out and also use google for more reference this error placed there intentionally try to find out it will teach you something.