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back ssh from firewalled hosts
host B (you) redirects a modem port (62220) to his local ssh. host A is a remote machine (the ones that issues the ssh cmd). once connected port 5497 is in listening mode on host B. host B just do a ssh 127.0.0.1 -p 5497 -l user and reaches the remote host'ssh. This can be used also for vnc and so on.

Disable graphical login on Solaris
With a full installation of Solaris 10, the graphical login and desktop will start by default. This command will disable that feature. To enable it again use: /usr/dt/bin/dtconfig -e

Find the processes that are on the runqueue. Processes with a status of
Want to know why your load average is so high? Run this command to see what processes are on the run queue. Runnable processes have a status of "R", and commands waiting on I/O have a status of "D". On some older versions of Linux may require -emo instead of -eo. On Solaris: ps -aefL -o s -o user -o comm | egrep "^O|^R|COMMAND"

Remove the first character of each line in a file

View advanced Sort options, Quick Reference Help Alias
Once you get into advanced/optimized scripts, functions, or cli usage, you will use the sort command alot. The options are difficult to master/memorize however, and when you use sort commands as much as I do (some examples below), it's useful to have the help available with a simple alias. I love this alias as I never seem to remember all the options for sort, and I use sort like crazy (much better than uniq for example). # Sorts by file permissions $ find . -maxdepth 1 -printf '%.5m %10M %p\n' | sort -k1 -r -g -bS 20% 00761 drwxrw---x ./tmp 00755 drwxr-xr-x . 00701 drwx-----x ./askapache-m 00644 -rw-r--r-- ./.htaccess # Shows uniq history fast $ history 1000 | sed 's/^[0-9 ]*//' | sort -fubdS 50% exec bash -lxv export TERM=putty-256color Taken from my http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html

Reverse SSH
this command from the source server and this follow in the destination server: ssh user@localhost -p 8888

Create QR codes from a URL.
QR codes are those funny square 2d bar codes that everyone seems to be pointing their smart phones at. Try the following... $ qrurl http://xkcd.com Then open qr.*.png in your favorite image viewer. Point your the bar code reader on your smart phone at the code, and you'll shortly be reading xkcd on your phone. URLs are not the only thing that can be encoded by QR codes... short texts (to around 2K) can be encoded this way, although this function doesn't do any URL encoding, so unless you want to do that by hand it won't be useful for that.

Enable verbose boot in Mac OS X Open Firmware

Backup with versioning
Apart from an exact copy of your recent contents, also keep all earlier versions of files and folders that were modified or deleted. Inspired by EVACopy http://evacopy.sourceforge.net

Adding formatting to an xml document for easier reading
Sometimes you're trying to read through an xml file to determine whats wrong with it and a tool had removed all the linebreaks. xmllint will go ahead and make it pretty for you.


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