Fill DHCP table.

dhcp-fill.rb

#!/usr/bin/env ruby
# Fill DHCP table.

require 'optparse'

options = {}

OptionParser.new do |opt|
  opt.banner = 'Usage: ruby dhcpfill.rb [options]'
	opt.on('-i', '--interface NAME', 'Network interface name') { |interface| options[:interface]=interface }
  opt.on('-m', '--mac XX:XX:XX:XX:XX:XX', 'Mac address. Default - random') { |mac| options[:mac]=mac }
  opt.on('-h', '--help', 'Displays Help') { puts opt }
end.parse!

rand_mac = (1..6).map { "%0.2x" % rand(256) }.join(':')
interface = options[:interface] if options[:interface]
rand_mac = options[:mac] if options[:mac]

if options[:interface]
  if rand_mac =~ /^([0-9a-fA-F]{2}[:-]){5}[0-9a-fA-F]{2}$/i
    puts `sudo ifconfig #{interface} down`
    puts `sudo ifconfig #{interface} up`
    puts `sudo ifconfig #{interface} hw ether #{rand_mac}`
    puts("New mac on #{interface}: #{rand_mac}")
  else
    puts 'Invalid mac-address'
  end
end