Live migration fails when the instance has a "config_drive" setting if environment uses Ceph

[Denis Kostryukov]

MOS 7.0 + Ceph

When I attempt to live-migrate my VM to another compute node, the VM tries to migrate but stays at the same compute node.
In the log I can see the following error:

2017-06-09 14:44:54.910 2450322 ERROR nova.virt.libvirt.driver [req-a6d67665-b861-4a62-b5bc-f5724e06c3af 1efd4d82bc434b78a6f3ced8836095ea 72662b64c4eb4a22b2f21828589e6ec5 - - -] [instance: 29695ed6-0f07-4e5b-94c7-9ccc16361278] Live Migration failure: Cannot access storage file '/var/lib/nova/instances/29695ed6-0f07-4e5b-94c7-9ccc16361278/disk.config' (as uid:111, gid:120): No such file or directory

2017-06-09 14:44:55.338 2450322 ERROR nova.virt.libvirt.driver [req-a6d67665-b861-4a62-b5bc-f5724e06c3af 1efd4d82bc434b78a6f3ced8836095ea 72662b64c4eb4a22b2f21828589e6ec5 - - -] [instance: 29695ed6-0f07-4e5b-94c7-9ccc16361278] Migration operation has aborted

#ll -lR /var/lib/nova/instances/29695ed6-0f07-4e5b-94c7-9ccc16361278
/var/lib/nova/instances/29695ed6-0f07-4e5b-94c7-9ccc16361278:

total 204
drwxr-xr-x 2 nova nova 76 Jun 9 14:42 ./
drwxr-xr-x 9 nova nova 4096 Jun 9 14:42 ../
-rw-rw---- 1 libvirt-qemu libvirt-qemu 0 Jun 9 14:42 console.log
-rw-r--r-- 1 libvirt-qemu libvirt-qemu 67108864 Jun 9 14:42 disk.config
-rw-r--r-- 1 nova nova 84 Jun 9 14:42 disk.info
-rw-r--r-- 1 nova nova 3295 Jun 9 14:42 libvirt.xml

In nova.conf:

config_drive_format=vfat

Then, I applied this fix: https://review.openstack.org/#/c/214773/
After that, for new VMs "disk.config" is created in Ceph pool "compute" and live-migrations works well.

Please create backport for MOS 7.0

The same fix for Master branch https://review.openstack.org/#/c/123073/

[Fuel Devops McRobotson (fuel-devops-robot)]

Fix proposed to branch: openstack-ci/fuel-7.0/2015.1.0
Change author: Michael Still <email address hidden>
Review: https://review.fuel-infra.org/35726