Open Stack

Hi all,

I¹m having trouble migrating a virtual instance to another host. I¹m
setting up a small private openstack environment. Currently I only have
two hosts; call them os1 and os2. Os1 is the controller and also a compute
node, and os2 is a compute node. There is one vm running on os2, and I'd
like to move it to os1 for reasons that are immaterial.

Currently I can¹t use nova¹s Œlive-migration¹ command, because the cpus
differ. Os1 has as an Intel Xeon E7-4807, and os2 has an Intel Xeon
E5-2620. I¹ve tried to use the `nova migrate` and the
`host-servers-migrate` commands which should, if my understanding is
correct, bring down the instance and then migrate it, but the instance
stays on os2. I should also mention that there is no shared storage for
the two hosts, that the instance was booted from qcow without any volumes,
and that the disk for this instance resides on
os2:/var/lib/nova/instances/<instance>/disk

I can think of a couple possible solutions:
1. Bring the instance down, change the libvirt.xml cpu model, bring the
instance up, and live-migrate
   - How do I find a lowest-common-denominator cpu?
   - Does openstack observe the Œmodel¹ parameter in the libvirt.xml? I
read that it didn¹t in the past.
2. Create a snapshot of the instance and boot it using the
‹availability-zone <zone>:<host> parameter

Is there any other way to do this? I read a blueprint from Juno about
adding a destination host parameter to the Œmigrate¹ command, but it seems
it was put on indefinite hold, and it isn¹t in Kilo. Is this something
that will be added?

Thanks!
Tyler