modern-web-design-and-development

8. Has Something Crashed?

Most Linux servers use Apache for the Web server software and MySQL for
the database. It is easy to see whether these are still running (and to restart
them if they’re not) or are using up way too much memory. To see all
processes running on your server right now, run this command:

admin@server$ ps aux | more

Scroll through the list and look for signs of apache (or its older name
httpd) and mysqld (the “d” stands for daemon and is related to the way
the programs are run). You are looking for something like this:

Or you can use the grep command to filter results:

admin@server$ ps aux | grep http

admin@server$ ps aux | grep mysql

If either Apache or MySQL is not running, then this is the source of the
problem.