Description of problem:
If you look in /etc/libvirt/libvirtd.conf on all the compute nodes you see the following action item:

###################################################################
# UUID of the host:
# Provide the UUID of the host here in case the command
# 'dmidecode -s system-uuid' does not provide a valid uuid. In case
# 'dmidecode' does not provide a valid UUID and none is provided here, a
# temporary UUID will be generated.
# Keep the format of the example UUID below. UUID must not have all digits
# be the same.

# NB This default all-zeros UUID will not work. Replace
# it with the output of the 'uuidgen' command and then
# uncomment this entry
#host_uuid = "00000000-0000-0000-0000-000000000000"

###################################################################


There might be problems with live migration if all hosts have the same uuid, as nova returns an error about "local migration".


How reproducible:
100%


Steps to Reproduce:
1. Deploy the overcloud
2. Look in /etc/libvirt/libvirtd.conf of any of the computes


Actual results:
host_uuid is not configured


Expected results:
Each host should have a unique host_uuid that was generated with the command 'uuidgen'