How to diagnose an unknown apache setup? I've been using mamp for a while now and everything has been working great. Then today I go to start it up and mamp alert tells me that apache is already running on that port and to pick another one. So without starting mamp, I type in local host in the web browser - my usual way to get to the sites that I'm developing - and a page pops up and it reads IT WORKS!, which tells me that I have an index.php file somewhere on my computer that echos It works!. But mamp is not running and I can't find this stupid it works file anywhere. Is there any way to diagnose this and perhaps kill this apache server so that I can start mamp back up without switching my ports?
You can use lsof to find out which processes are listening on which ports.

For example:

lsof -Pnl +M -i4 | grep ":80"


(assuming the process is running on port 80)

You can then use ps to figure out the name of the process for that processID:

ps -p &lt;pid&gt;