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Generate a Random (unicast) MAC address

Terminal - Generate a Random (unicast) MAC address
openssl rand -hex 1 | tr '[:lower:]' '[:upper:]' | xargs echo "obase=2;ibase=16;" | bc | cut -c1-6 | sed 's/$/00/' | xargs echo "obase=16;ibase=2;" | bc | sed "s/$/:$(openssl rand -hex 5 | sed 's/\(..\)/\1:/g; s/.$//' | tr '[:lower:]' '[:upper:]')/"
2013-10-22 08:40:46
User: 4fd
Functions: bc cut echo sed tr xargs
0
Generate a Random (unicast) MAC address

I did not come up with this one myself, but found this somewhere else several months ago.

Alternatives

There are 3 alternatives - vote for the best!

Terminal - Alternatives
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
17

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)

openssl rand -hex 6 | sed 's/\(..\)/\1:/g; s/.$//'
2010-09-23 02:31:12
User: putnamhill
Functions: sed
Tags: sed xxd openssl
15

Use the following variation for FreeBSD:

openssl rand 6 | xxd -p | sed 's/\(..\)/\1:/g; s/:$//'
hexdump -n6 -e '/1 ":%02X"' /dev/random|sed s/^://g
2015-01-19 03:09:43
User: rubo77
Functions: hexdump sed
3

Generate a random MAC address with capital letters

od -An -N10 -x /dev/random | md5sum | sed -r 's/^(.{10}).*$/\1/; s/([0-9a-f]{2})/\1:/g; s/:$//;'
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
2

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]

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