Commands by bandie91 (21)

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Display the size of all your home's directories
Display the size (human reading) of all the directories in your home path (~).

Getting started with tcpdump
At some point you want to know what packets are flowing on your network. Use tcpdump for this. The man page is obtuse, to say the least, so here are some simple commands to get you started. -n means show IP numbers and don't try to translate them to names. -l means write a line as soon as it is ready. -i eth0 means trace the packets flowing through the first ethernet interface. src or dst w.x.y.z traces only packets going to or from IP address w.x.y.z. port 80 traces only packets for HTTP. proto udp traces only packets for UDP protocol. Once you are happy with each option combine them with 'and' 'or' 'not' to get the effects you want.

load changes without logging in and out vim
src: daily vim blog

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Display IPs accessing your Apache webserver.

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

find out how many days since given date
You can also do this for seconds, minutes, hours, etc... Can't use dates before the epoch, though.

Dump a configuration file without comments or whitespace...
A short, *easy-er* to remember command for stripping whitespace and comments from a config file, (or any file for that matter). Remember regex as: slash, space, star. pound, slash, bar. pointy-hat, dollar. (or "caret, dollar" if you must) :-P

Analyze awk fields
translate and number lines is simpler and you use tr to choose your delimiter (eg for csv files)


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