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May 19, 2015 - A Look At The New Commandlinefu
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generate random mac address

Terminal - generate random mac address
2>/dev/null dd if=/dev/urandom bs=1 count=6 | od -t x1 | sed '2d;s/^0\+ //;s/ /:/g'
2010-04-30 00:44:21
User: jianingy
Functions: dd od sed
generate random mac address


There are 5 alternatives - vote for the best!

Terminal - Alternatives
2>/dev/null dd if=/dev/urandom bs=1 count=6 | od -t x1|sed '2d;s/0000000 *//;s/ /:/g;s/::*$//'
2010-04-30 16:57:59
User: hckhckhck
Functions: dd od sed

Mac OS X needs some clean up. First command works in Linux, Solaris just needs the "0000000"'s removed

Know a better way?

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What others think


Comment by buzzy 411 weeks and 3 days ago

This may require some filtering. There are a few mask bits at the beginning such as the multicast bit. If you've ever tried changing a MAC address from "00:aa:bb:cc:dd:ee" to "01:aa:bb:cc:dd:ee", you may have noticed some devices like Cisco switches become unhappy. Probably better to leave the first byte set to "00" and just generate 5 random bytes.

Comment by mulad 411 weeks and 3 days ago

Your point of view

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