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run command on a group of nodes in parallel redirecting outputs
Do the same as pssh, just in shell syntax. Put your hosts in hostlist, one per line. Command outputs are gathered in output and error directories.

Find longest running non-root processes on a machine
If you have ever been trying to look for a list of processes based on their elapsed time you don't need to look any further. This command lets you find the list of processes ordered in a reversed order (oldest at the top) that have been running for over an hour on your system. Any system processes are filtered out, leaving only user initiated ones in. I find it extremely useful for debugging and performance analysis.

check open ports without netstat or lsof

Big (four-byte) $RANDOM
Sometimes, in a shell script, you need a random number bigger than the range of $RANDOM. This will print a random number made of four hex values extracted from /dev/urandom.

Grab all .flv files from a webpage to the current working directory
I wanted all the 'hidden' .flv files from the http link in the command line; wget seemed appropriate, fed with output from lynx, grep the flv files and the normalised via sed (to remove the numeric bullet). Similar to the 'Grab mp3 files' fu. Replace link with your own, grep arg with something more interesting ;) See here for something along the same lines... http://www.commandlinefu.com/commands/view/1006/grab-mp3-files-from-your-favorite-netcasts-mp3blog-or-sites-that-often-have-good-mp3s Hope you find it useful! Improvements welcome, naturally.

Copy ssh keys to user@host to enable password-less ssh logins.
Same as original just no $ at start

Write on the console without being registered
just use a space to prevent commands from being recorded in bash's history on most systems

Get AWS temporary credentials ready to export based on a MFA virtual appliance
You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

Make a thumbnail image of first page of a PDF.
convert is included in ImageMagick. Don't forget the [X] (where X is the page number). [0] is the first page of the PDF.

Loops over files, runs a command, dumps output to a file
In this case I'm selecting all php files in a dir, then echoing the filename and piping it to ~/temp/errors.txt. Then I'm running my alias for PHPCS (WordPress flags in my alias), then piping the PHPCS output to grep and looking for GET. Then I'm piping that output to the same file as above. This gets a list of files and under each file the GET security errors for that file. Extrapolate this to run any command on any list of files and pipe the output to a file. Remove the >> ~/temp/errors.txt to get output to the screen rather than to a file.


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