Installation guide

Generating a new unique MAC address
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To lock the virtual CPUs to the second NUMA node (CPUs four to seven), run the following
commands.
# virsh vcpupin guest1 0 4
# virsh vcpupin guest1 1 5
# virsh vcpupin guest1 2 6
# virsh vcpupin guest1 3 7
The virsh vcpuinfo command confirms the change in affinity.
# virsh vcpuinfo guest1
VCPU: 0
CPU: 4
State: running
CPU time: 32.2s
CPU Affinity: ----y---
VCPU: 1
CPU: 5
State: running
CPU time: 16.9s
CPU Affinity: -----y--
VCPU: 2
CPU: 6
State: running
CPU time: 11.9s
CPU Affinity: ------y-
VCPU: 3
CPU: 7
State: running
CPU time: 14.6s
CPU Affinity: -------y
Information from the KVM processes can also confirm that the guest is now running on the second
NUMA node.
# grep pid /var/run/libvirt/qemu/guest1.xml
<domstatus state='running' pid='4907'>
# grep Cpus_allowed_list /proc/4907/task/*/status
/proc/4907/task/4916/status:Cpus_allowed_list: 4
/proc/4907/task/4917/status:Cpus_allowed_list: 5
/proc/4907/task/4918/status:Cpus_allowed_list: 6
/proc/4907/task/4919/status:Cpus_allowed_list: 7
</section>
24.5. Generating a new unique MAC address
In some case you will need to generate a new and unique MAC address for a guest. There is no
command line tool available to generate a new MAC address at the time of writing. The script
provided below can generate a new MAC address for your guests. Save the script to your guest as
macgen.py. Now from that directory you can run the script using ./macgen.py and it will generate a
new MAC address. A sample output would look like the following:
$ ./macgen.py
00:16:3e:20:b0:11
#!/usr/bin/python
# macgen.py script to generate a MAC address for virtualized guests
#
import random
#
def randomMAC():