Generat a Random MAC address

MAC=`(date; cat /proc/interrupts) | md5sum | sed -r 's/^(.{10}).*$/\1/; s/([0-9a-f]{2})/\1:/g; s/:$//;'`
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)
Sample Output
00:12:2F:22:32:16

17
By: vaporub
2009-02-16 07:09:43

10 Alternatives + Submit Alt

  • Use the following variation for FreeBSD: openssl rand 6 | xxd -p | sed 's/\(..\)/\1:/g; s/:$//'


    15
    openssl rand -hex 6 | sed 's/\(..\)/\1:/g; s/.$//'
    putnamhill · 2010-09-23 02:31:12 0
  • Generate a random MAC address with capital letters


    3
    hexdump -n6 -e '/1 ":%02X"' /dev/random|sed s/^://g
    rubo77 · 2015-01-19 03:09:43 0

  • 2
    od -An -N10 -x /dev/random | md5sum | sed -r 's/^(.{10}).*$/\1/; s/([0-9a-f]{2})/\1:/g; s/:$//;'
    unixmonkey12364 · 2010-09-23 00:15:30 1
  • 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


    2
    od /dev/urandom -w6 -tx1 -An|sed -e 's/ //' -e 's/ /:/g'|head -n 1
    karel1980 · 2011-05-16 15:05:34 1
  • Generates labyrinth-like pattern on UTF-8 terminal in bash. For fun ;) Show Sample Output


    2
    while ( true ) ; do if [ $(expr $RANDOM % 2 ) -eq 0 ] ; then echo -ne "\xE2\x95\xB1" ; else echo -ne "\xE2\x95\xB2" ; fi ; done
    tobi · 2015-01-17 12:46:37 3

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}).*$/\1/; s/([0-9a-f]{2})/\1:/g; s/:$//;'`
aorth · 351 weeks and 5 days ago
Beware, completely random MACs are not guaranteed to be "unicast"
outly3r · 328 weeks and 2 days ago

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

You must be signed in to comment.

Considering A New Car?

You should consider a Tesla. Get 6 Months Free Supercharging.

Free Supercharging

What's this?

commandlinefu.com is the place to record those command-line gems that you return to again and again. That way others can gain from your CLI wisdom and you from theirs too. All commands can be commented on, discussed and voted up or down.

Share Your Commands



Stay in the loop…

Follow the Tweets.

Every new command is wrapped in a tweet and posted to Twitter. Following the stream is a great way of staying abreast of the latest commands. For the more discerning, there are Twitter accounts for commands that get a minimum of 3 and 10 votes - that way only the great commands get tweeted.

» http://twitter.com/commandlinefu
» http://twitter.com/commandlinefu3
» http://twitter.com/commandlinefu10

Subscribe to the feeds.

Use your favourite RSS aggregator to stay in touch with the latest commands. There are feeds mirroring the 3 Twitter streams as well as for virtually every other subset (users, tags, functions,…):

Subscribe to the feed for: