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Generat a Random MAC address

Terminal - Generat a Random MAC address
MAC=`(date; cat /proc/interrupts) | md5sum | sed -r 's/^(.{10}).*$/\1/; s/([0-9a-f]{2})/\1:/g; s/:$//;'`
2009-02-16 07:09:43
User: vaporub
Functions: cat md5sum sed
14
Up
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Generat a Random MAC address

Original author unknown (I believe off of a wifi hacking forum).

Used in conjuction with ifconfig and cron.. can be handy (especially spoofing AP's)

Show sample output | Add to favourites | Report as malicious

Alternatives

There are 9 alternatives - vote for the best!

Terminal - Alternatives
openssl rand -hex 6 | sed 's/\(..\)/\1:/g; s/.$//'
2010-09-23 02:31:12
User: putnamhill
Functions: sed
Tags: sed xxd openssl
9
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Down
Generate a Random MAC address

Use the following variation for FreeBSD:

openssl rand 6 | xxd -p | sed 's/\(..\)/\1:/g; s/:$//'
Comments (0) | Add to favourites | Report as malicious
od -An -N10 -x /dev/random | md5sum | sed -r 's/^(.{10}).*$/\1/; s/([0-9a-f]{2})/\1:/g; s/:$//;'
2010-09-23 00:15:30
User: unixmonkey12364
Functions: md5sum od sed
2
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Down
Generat a Random MAC address
Comments (1) | Add to favourites | Report as malicious
od /dev/urandom -w6 -tx1 -An|sed -e 's/ //' -e 's/ /:/g'|head -n 1
2011-05-16 15:05:34
User: karel1980
Functions: head od sed
1
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Generat a Random MAC address

Just increase the 1 at the end if you want to generate more than one.

(Alternative to "| head -n N" you could use the -b flag of od: -b $[6*N]

Show sample output | Comments (1) | Add to favourites | Report as malicious
2>/dev/null dd if=/dev/urandom bs=1 count=6 | od -t x1 |sed '2d;s/^0\+ //;s/ /:/g'
2011-05-17 21:04:35
User: flyc0r
Functions: dd od sed
0
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Down
Generat a Random MAC address
Comments (0) | Add to favourites | Report as malicious
MAC=$((date +'%Y%m%d%H%M%S%N'; cat /proc/interrupts) | md5sum | sed -r 's/(..)/\1:/g' | cut -d: -f 1-6)
2011-07-14 13:11:50
User: jazznjam
Functions: cat cut date md5sum sed
0
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Generat a Random MAC address

I liked vaporub's suggestion, here a little simplification of the sed command.

Comments (0) | Add to favourites | Report as malicious

Know a better way?

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What others think

The current top example (by vaporub) generates an invalid MAC address (should be six groups of two hexadecimal digits). Just use 12 in the regex instead:

MAC=`(date; cat /proc/interrupts) | md5sum | sed -r 's/^(.{12}).*$/\1/; s/([0-9a-f]{2})/\1:/g; s/:$//;'`
Comment by aorth 9 weeks and 2 days ago

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