Commands tagged tcpdump (25)

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Randomly run command
Randomly decide whether to run a command, or fail. It's useful for testing purposes. . Usage: ran PERCENTAGE COMMAND [ARGS] Note: In this version the percentage is required. . This is like @sesom42 and @snipertyler's commands but in a USABLE form. . e.g. In your complicated shell script, put "ran 99" before a crucial component. Now, it will fail 1% of the time allowing you to test the failure code-path. $ ran 99 my_complex_program arg1 arg2

Diff two directories by finding and comparing the md5 checksums of their contents.
Compares the md5 checksums of the contents of two directories, outputting the checksum and filename where any files differ. Shows only the file name, not the full path.

Watch active calls on an Asterisk PBX
Show active calls as the happen on an Asterisk server. Note that the Asterisk command (in single quotes) is formatted for Asterisk 1.6. Use the -n flag on the watch command to modify the refresh period (in seconds - default is 2 seconds).

Create a file of repeated, non-zero
dd can be used with /dev/zero to easily create a file of all zero-bytes. Pipe that through tr and use octal conversions to change the byte values from zero to 0xff (octal 0377). You can replace 0377 with the byte of your choice. You can also use \\0 and \\377 instead of the quoted version.

Automatically tunnel all ports of running docker instances in boot2docker
It requires, that comes with brew: brew install jq

most used unix commands

Change string in many files at once and more.
Find all files that contain string XXX in them, change the string from XXX to YYY, make a backup copy of the file and save a list of files changed in /tmp/fileschanged.

Get all IPs via ifconfig
Fetches the IPs and ONLY the IPs from ifconfig. Simplest, shortest, cleanest. Perl is too good to be true... (P.S.: credit should go to Peteris Krumins at

Destroy all disks on system simultaneously
This command will use the fdisk utility to find all block devices on your system, and overwrite them with data from the /dev/urandom non-blocking random number generator. CAUTION: This will irrevocably erase EVERY SINGLE physical block storage device visible to the fdisk utility, including plugged USB devices, RAID sets, LVM, etc.

The scene in the Shining (Stanley Kubrick)
Let's take a rest. How about watch a horror? The Shining

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