Ports
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Jump to navigationJump to searchSay you want to know what is running on port 80 of your machine. The first hint would be to look in the file /etc/services to get an idea of what typically runs on that port.
http 80/tcp www www-http #World Wide Web HTTP http 80/udp www www-http #World Wide Web HTTP
looks like it's the port typically used for the www. Now we can try netstat to actually see what is listening, not just what should be there.
netstat -an | grep LISTEN
however I prefer the flexibility of lsof which I install on all of my machines.
lsof -i:80
will show you exactly what is listening on this port.