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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

Bash prompt with user name, host, history number, current dir and just a touch of color
I put that line in my .bash_profile (OS X) and .bashrc (Linux). Here is a summary of what the \char means: n=new line, u=user name, h=host, !=history number, w=current work directory The \[\e[32m\] sequence set the text to bright green and \[\e[0m\] returns to normal color. For more information on what you can set in your bash prompt, google 'bash prompt'

Rescan partitions on a SCSI device
Used this after cloning a disk with dd to make the newly written partitions show up in /dev/

Monitor memory usage
Monitor with watch command and vmstat, memory usage

Filter the output of a file continously using tail and grep
The OPs solution will work, however on some systems (bsd), grep will not filter the data, unless the --line-buffered option is enabled.

Adding Prefix to File name
Good old bracket expansion :-) For large numbers of files, "rename" will spare you the for-loop, or the find/exec...

Change every instance of OLD to NEW in file FILE
Very quick way to change a word in a file. I use it all the time to change variable names in my PHP scripts (sed -i 's/$oldvar/$newvar/g' index.php)

geoip information
Not my script. Belongs to mathewbauer. Used without his permission. This script gives a single line as shown in the sample output. NOTE: I have blanked out the IP address for obvious security reasons. But you will get whatever is your IP if you run the script. Tested working in bash.

Use md5sum to check your music and movie files. Also use diff.
This is a beginning script. You can create a file with > filename. You can also use diff to compare output run at different times to verify no change in your files. I apologize in advance if this is too simple. For some it should be a start.


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