Computer Tips - What's an alternate way to see network activity?

Date: 2008apr15 OS: Linux Q. What's an alternate way to see network activity? A. Use lsof - which stands for List Open Files. Sounds weird, huh? But on Linux/Unix everything is a file -- even network connections! Here are some some uses. All TCP/IP connections:
lsof | grep TCP
All IPv6 connections:
lsof | grep IPv6
Or
lsof -i6
If you don't want any IPv6 running see my tip on disabling it: http://www.davekb.com/search.php?target=disable+IPv6 What's Apache doing:
lsof | grep httpd
(Lists files it has open and network connections - nice) lsof has many options. But I prefer simply grep-ing. If you aren't root some files will be unavailable.