Libvirt-NOVA-Bug-Live-Migration.txt

ALERT TO ALL UBUNTU USERS (AND POTENTIALLY, CENTOS USERS)

There is a confirmed BUG (https://bugs.launchpad.net/nova/+bug/1576093) affecting Live Migration (block and non-block) when Libvirt 1.3.1 is used (this means: Ubuntu 14.04lts with ubuntu-cloud-archive repos for Mitaka).

This bug prevents the use of tunneled live migration. 

By the moment, and until the bug is corrected and new nova and/or libivrt packages are released, the workaround is to disable apparmor in libvirt and tunneled live migrations with the following commands (Ubuntu Server 14.04lts):

aa-disable /etc/apparmor.d/usr.sbin.libvirtd
/etc/init.d/libvirt-bin restart
crudini --del /etc/nova/nova.conf libvirt live_migration_flag
crudini --del /etc/nova/nova.conf libvirt block_migration_flag
crudini --set /etc/nova/nova.conf libvirt live_migration_tunnelled False
openstack-control.sh restart nova

If you already have running instances, either perform a normal migration on them or hard-reboot them so libvirt will reconstruct their XML definitions.

While this is only happening in Ubuntu 14.04 lts at this time, if you encounter this in Centos, please use the following commands:

crudini --del /etc/nova/nova.conf libvirt live_migration_flag
crudini --del /etc/nova/nova.conf libvirt block_migration_flag
crudini --set /etc/nova/nova.conf libvirt live_migration_tunnelled False
openstack-control.sh restart nova

Keep and eye on the bug at the following links:

https://bugs.launchpad.net/nova/+bug/1576093
https://review.openstack.org/#/c/310707/

The current versions in Ubuntu 14.04 with ubuntu cloud archive repo which are affected by this bug are:

Libvirt:

libvirt-bin                         1.3.1-1ubuntu10~cloud0
libvirt-doc                         1.3.1-1ubuntu10~cloud0
libvirt0:amd64                      1.3.1-1ubuntu10~cloud0
python-libvirt                      1.3.1-1ubuntu1~cloud0

Nova:

nova-common                         2:13.0.0-0ubuntu2~cloud0
nova-compute                        2:13.0.0-0ubuntu2~cloud0
nova-compute-kvm                    2:13.0.0-0ubuntu2~cloud0
nova-compute-libvirt                2:13.0.0-0ubuntu2~cloud0

END.-