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Generat a Random MAC address

Terminal - Generat a Random MAC address
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
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]

Alternatives

There are 5 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
15

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
14

Use the following variation for FreeBSD:

openssl rand 6 | xxd -p | sed 's/\(..\)/\1:/g; s/:$//'
od -An -N10 -x /dev/random | md5sum | sed -r 's/^(.{10}).*$/\1/; s/([0-9a-f]{2})/\1:/g; s/:$//;'
od -An -N6 -tx1 /dev/urandom | sed -e 's/^ *//' -e 's/ */:/g' -e 's/:$//' -e 's/^\(.\)[13579bdf]/\10/'
2012-08-31 13:15:03
User: outly3r
Functions: od sed
0

- The last sed expression ensures the unicast/multicast bit is set to zero

- The greedy space replacements are for portability across UNIX seds (note there's TWO spaces and not just one, as this web shows, in s/^ */)

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

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

Know a better way?

If you can do better, submit your command here.

What others think

@karel1980

you have forgot to add the second ':' ... never mind, thx anyway

od /dev/urandom -w6 -tx1 -An|sed -e 's/ //' -e 's/ /::/g'|head -n 1

Comment by momitov 179 weeks and 3 days ago

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