[dundee] Virtual Xen Network Interfaces

[Andrew Clayton]

On Wed, 29 Oct 2008 15:50:38 +0000, gordon dunlop wrote:

> When a Xen virtual machine is created a virtual MAC address is
> generated into the Xen virtual machine configuration file. Some people
> like to do configure this virtual MAC address for different reasons.
> All Xen virtual MAC addresses are 00:16:3e:xxx:xx:xx, potentially
> approx 12 million MAC addresses. I was looking in how to produce a
> python script that could randomly generate these virtual addresses
> with a user input defining the number of addresses to generate. I am
> stuck as I can only produce copies of the one MAC address due to the
> random generator only executing once. I have tried to use loops and
> iterations to produce the different MAC addresses but to no avail.
> Here is what I have got to so far in my Python script.
> 
> #!/usr/bin/python
> # xenvirtualmac.py - Generating virtual MAC Addresses with user input
> #
> import random
> mac = [ 0x00, 0x16, 0x3e,
> random.randint(0x00, 0x7f),
> random.randint(0x00, 0xff),
> random.randint(0x00, 0xff) ]
> n = int(raw_input('Enter number of MAC Addresses: '))
> i = iter(mac)
> for j in range(1,n + 1):
>      print 'MAC Addresses', j, ':'.join(map(lambda x: "%02x" % x,
> mac))
> 
> If anyone has ideas please let me know.

This seems to work

#!/usr/bin/python
# xenvirtualmac.py - Generating virtual MAC Addresses with user input
#
import random
n = int(raw_input('Enter number of MAC Addresses: '))
for j in range(1,n + 1):
	mac = [ 0x00, 0x16, 0x3e,
		random.randint(0x00, 0xff),
		random.randint(0x00, 0xff),
		random.randint(0x00, 0xff) ]

	print 'MAC Addresses', j, ':'.join(map(lambda x: "%02x" % x, mac))