I’ll do this from time to time when I come across some tidbits of information that I find useful to me.
- pgrep and pkill – The first command will return the pid (process id) based on a name or other attribute. pkill will signal a process with a patching name or attribute. So if you want to kill processes being run by a user per say, you would execute a pkill -U USERNAME.
- lsof – This command is usually pretty well known to most SysAdmins. It allows us to see any files that are currently open on a particular filesystem. It’s great for tracking down files that are locked open by processes or users, or finding files that have been deleted, but still alive for reasons I just mentioned.
- iptraf – If you ever wanted to know where your traffic goes to and comes from, yum/apt-get install this sucker. While you don’t get packet break down like you would from an app like WireShark, it’s still a pretty cool tool to track network traffic.
- htop – This is like top on steroids. Great tool that can be yum installed if you have rpmforge repos setup.