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Generate random valid mac addresses

Terminal - Generate random valid mac addresses
for i in {1..6}; do printf "%0.2X:" $[ $RANDOM % 0x100 ]; done | sed 's/:$/\n/'
2010-12-07 19:26:58
User: forcefsck
Functions: printf sed
2
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Generate random valid mac addresses

Shorter and more straightforward.

Also in perl:

perl -e 'print join(":", map { sprintf "%0.2X",rand(256) }(1..6))."\n"'
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Alternatives

There are 2 alternatives - vote for the best!

Terminal - Alternatives
ruby -e 'puts (1..6).map{"%0.2X"%rand(256)}.join(":")'
2010-12-08 10:01:31
User: eightmillion
Tags: Network bash mac ruby
3
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Generate random valid mac addresses

Ruby version.

Also, a perl version:

perl -e 'printf("%.2x.",rand(255))for(1..5);printf("%.2x\n",rand(255))'
Comments (1) | Add to favourites | Report as malicious
for i in {0..1200}; do for i in {1..12} ; do echo -n ${hexchars:$(( $RANDOM % 16 )):1} ; done | sed -e 's/\(..\)/:\1/g' | sed 's/.\(.*\)/\1/' ; echo; done
2010-12-04 16:44:11
User: Raymii
Functions: echo sed
Tags: Network bash sed mac
2
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Generate random valid mac addresses

First set the variable $hexchars:

hexchars="0123456789ABCDEF"

Change the number in the first for loop if you need less then 1200 mac addresses

Show sample output | Comments (0) | Add to favourites | Report as malicious
h=0123456789ABCDEF;for c in {1..12};do echo -n ${h:$(($RANDOM%16)):1};if [[ $((c%2)) = 0 && $c != 12 ]];then echo -n :;fi;done;echo
2010-12-05 01:35:03
User: dabom
Functions: echo
Tags: Network bash mac
2
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Generate random valid mac addresses

Doubt it actually generates valid mac addresses but this version doesn't need any external commands so it runs much faster.

Much shorter as well.

Show sample output | Comments (0) | Add to favourites | Report as malicious
python -c "from itertools import imap; from random import randint; print ':'.join(['%02x'%x for x in imap(lambda x:randint(0,255), range(6))])"
2010-12-08 11:02:16
User: ohe
Functions: python
Tags: Network bash mac
1
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Generate random valid mac addresses

Python Alternative

Show sample output | Comments (1) | Add to favourites | Report as malicious
macchanger -A (nic)
2010-12-07 20:22:54
User: pebkac
Tags: Network bash mac
0
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Generate random valid mac addresses

You have to install the package macchanger but this command will create a random mac from a list of known manufacturers. If you want to make a complete random mac, use the -r option .

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