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I want to run a web application on my local OSX Lion machine. When I go to http://localhost:8080 there is already a process running so I get the following message:

Status Code: 404

Exception: Request URL / not found.<br><br>

Generated by Winstone Servlet Engine v0.9.10 at Wed Nov 30 13:01:15 CET 2011

How can I find the process that runs on this port under OSX. I found several entries that do the same on Linux but they do not seem to work in OSX.

Thanks a lot.

Update 1: I running the command lsof -i -P | grep 8080 results in the following output

WebProces 174 petersmith   20u  IPv6 0xffffff80147e6cc0      0t0  TCP localhost:50059->localhost:8080 (ESTABLISHED)

But this does not tell me which process is responsible for creating the html output that I get in my browser, when accessing the URL

Update 2: I should mention that I want to install Jenkins CI on my machine and there is already an installation present which seems to have a problem on my machine.

share|improve this question
@slhck I did this and updated my answer, but it does not tell me which process is currently running. Curiously lsof -i tcp:8080 does not result in anything... – Besi Nov 30 '11 at 12:18
@slhck Seems you're reading my mind. Your link fixed my problem, if you post an Answer I'll happily accept it. Thanks! – Besi Nov 30 '11 at 13:02
up vote 8 down vote accepted

In a very general way:

sudo lsof -i -P

… will list you all processes running on certain ports. See this answer for more details.

In your special case, Jenkins is already running. This Stack Overflow question has more information: Can not run Jenkins on Mac. The solution seems to be:

sudo launchctl unload /Library/LaunchDaemons/org.jenkins-ci.plist

… which is also related to the similar Stack Overflow question: How to stop Jenkins installed on Mac Snow Leopard?

share|improve this answer
curiously lsof did not reveal that it was the Jenkins binary that was "occupying" port 8080 – Besi Dec 2 '11 at 9:08
Ah, you know why? Because it's probably a system process and you need to run sudo lsof. My bad. Fixed the answer! – slhck Dec 2 '11 at 9:11
Correct, there we go: java 54 jenkins 135u IPv6 0xffffff8014817e80 0t0 TCP *:8080 (LISTEN) – Besi Dec 2 '11 at 12:25

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