Generates a random mac address with real OUI

random_mac.py

import random

# wget http://standards-oui.ieee.org/oui.txt
OUI_FILE = 'oui.txt'
SEP = ':'

with open(OUI_FILE) as f:
    lines = f.readlines()

while True:
    line = random.choice(lines)
    if 'base 16' in line:
        oui_b16 = line[0:6]
        vendor = line[20:].strip()
        break

lower_bits = "%x" % random.randint(0x100000, 0xffffff-1)
lower_bits = lower_bits.upper()

mac_b16 = oui_b16 + lower_bits
mac = SEP.join([mac_b16[i:i+2] for i in range(0, 12, 2)])

#print vendor
print mac