Port 80 required by Tomcat v7.0 Server at localhost is already in use

Question

I'm using Fedora I downloaded Tomcat 7 (apache-tomcat-7.0.34 , [url]http://www.coreservlets.com/Apache-Tomcat-Tutorial/tomcat7-files/tomcat-7.0.34-preconfigured.zip[/url]) and then add it to eclipse(Eclipse Java EE IDE for Web Developers. Version: Helios Release Build id: 20100617-1415). I want to start it from

but I get the following error:

Port 80 required by Tomcat v7.0 Server at localhost is already in use. The server may already be running in another process, or a system process may be using the port. To start this server you will need to stop the other process or change the port number(s).

I checked which process is working on port 80

[CODE] netstat -an|grep 80 ps -aux|grep tomcat [/CODE]

and there is no process is working on port 80. There is no tomcat running.

also I checked with lsof

# lsof -p :80
lsof: illegal process ID: :80
lsof 4.86
latest revision: ftp://lsof.itap.purdue.edu/pub/tools/unix/lsof/
latest FAQ: ftp://lsof.itap.purdue.edu/pub/tools/unix/lsof/FAQ
latest man page:   ftp://lsof.itap.purdue.edu/pub/tools/unix/lsof/lsof_man
usage: [-?abhKlnNoOPRtUvVX] [+|-c c] [+|-d s] [+D D] [+|-f[gG]] [+|-e s]
 [-F [f]] [-g [s]] [-i [i]] [+|-L [l]] [+m [m]] [+|-M] [-o [o]] [-p s]
[+|-r [t]] [-s [p:s]] [-S [t]] [-T [t]] [-u s] [+|-w] [-x [fl]] [--]     [names]
Use the ``-h'' option to get more help information.

# lsof -t -i:80
#

what are potential problem? thanks

why not just running on 8080? Check if you have Apache2, it could be running on Port 80 — JohnnyAW
What do you see when you open http://127.0.0.1 in your web browser? — Axel

Henry Henry · Accepted Answer · 2015-11-14T10:13:44

If you run eclipse on a Linux box, you most likely don't do that as root. In this case you can't open ports below 1024.

Port 80 required by Tomcat v7.0 Server at localhost is already in use

2 Answers