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Generate a Random MAC address

Terminal - Generate a Random MAC address
macchanger --random interface
2010-09-26 11:12:31
User: JulianTosh
-4
Generate a Random MAC address

macchanger will allow you to change either 1) mfg code, 2) host id, or 3) all of the above. Use this at wifi hotspots to help reduce profiling.

Alternatives

There is 1 alternative - 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
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]

Know a better way?

If you can do better, submit your command here.

What others think

I'd love the ability to just print the address with this command rather than try to apply it directly.

Comment by rthemocap 248 weeks and 2 days ago

rthemocap, if you use the -s option, it will simply print the generated mac and exit.

Comment by JulianTosh 248 weeks and 1 day ago

Your point of view

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