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check open ports without netstat or lsof

Scan Network for Rogue APs.
I've used this scan to sucessfully find many rogue APs on a very, very large network.

Remove BOM (Byte Order Mark) from text file
Takes file (text.txt), removes BOM from it, and outputs the result to a new file (newFile.txt). BOM is "Byte Order Mark" ([http://en.wikipedia.org/wiki/Byte_order_mark]), an invisible, non-breaking, zero-length character. In other words, if you see a DIFF with "" at the beginning, you've got a byte order mark, which can't be removed without this command or a hex editor. It can appear for a number of reasons, such as getting copied to/from a UNIX filesystem...

Faster find and move using the find and xargs commands. Almost as fast as locate.
Only tested on Linux Ubunty Hardy. Works when file names have spaces. The "-maxdepth 2" limits the find search to the current directory and the next one deeper in this example. This was faster on my system because find was searching every directory before the current directory without the -maxdepth option. Almost as fast as locate when used as above. Must use double quotes around pattern to handle spaces in file names. -print0 is used in combination with xargs -0. Those are zeros not "O"s. For xargs, -I is used to replace the following "{}" with the incoming file-list items from find. Echo just prints to the command line what is happening with mv. mv needs "{}" again so it knows what you are moving from. Then end with the move destination. Some other versions may only require one "{}" in the move command and not after the -I, however this is what worked for me on Ubuntu 8.04. Some like to use -type f in the find command to limit the type.

List all active access_logs for currently running Apache or Lighttpd process
Ever logged into a *nix box and needed to know which webserver is running and where all the current access_log files are? Run this one liner to find out. Works for Apache or Lighttpd as long as CustomLog name is somewhat standard. HINT: works great as input into for loop, like this: $ for i in `lsof -p $(netstat -ltpn|awk '$4 ~ /:80$/ {print substr($7,1,index($7,"/")-1)}')| awk '$9 ~ /access.log$/ {print $9| "sort -u"}'` ; do echo $i; done Very useful for triage on unfamiliar servers!

Figure out what shell you're running

list block devices
Shows all block devices in a tree with descruptions of what they are.

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"

edit hex mode in vim
return to normal mode from hex mode :%!xxd -r

Find directory depth
Returns a the directory depth.


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