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List all installed PERL modules by CPAN
This command will give you the detailed information about the installed perl modules i.e. installed path, Link type, version, files etc.

The BOFH Excuse Server

Find usb device in realtime
Using this command you can track a moment when usb device was attached.

Generate a ZenCart-style MD5 password hash.
ZenCart uses a MD5 with a salt to secure its passwords. If you need to forcibly change someone's password to a known value within the database, this one-liner can generate the password. Change the value of 'p' to the password you want.

Redirect bash built-in output to stdout
I've had a horrible time trying to pipe the output of some shell built-ins like 'time' to other programs. The built-in doesn't output to stdout or stderr most of the time but using the above will let you pipe the output to something else.

Intercept, monitor and manipulate a TCP connection.
Forwards localhost:1234 to machine:port, running all data through your chain of piped commands. The above command logs inbound and outbound traffic to two files. Tip: replace tee with sed to manipulate the data in real time (use "sed -e 's/400 Bad Request/200 OK/'" to tweak a web server's responses ;-) Limitless possibilities.

Find Duplicate Files (based on size first, then MD5 hash)
Finds duplicates based on MD5 sum. Compares only files with the same size. Performance improvements on: $find -not -empty -type f -printf "%s\n" | sort -rn | uniq -d | xargs -I{} -n1 find -type f -size {}c -print0 | xargs -0 md5sum | sort | uniq -w32 --all-repeated=separate The new version takes around 3 seconds where the old version took around 17 minutes. The bottle neck in the old command was the second find. It searches for the files with the specified file size. The new version keeps the file path and size from the beginning.

VMware Server print out the state of all registered Virtual Machines.
I use this command on my machines running VMware Server to print out the state of all registered Virtual machines.

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 total Terabytes written to a SSD
You must have smartmontools installed for this to work. This also assumes you 512 byte sector sizes, this is pretty standard.


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