[Gluster-users] qemu with gfapi and live-migration

[Stephan Holljes]

Hello,

we have a setup of two machines building a GlusterFS cluster. We run
qemu/kvm for virtual machines. The image-files are in a GlusterFS volume.
So far we have been successfully using the fuse-client to access the images
and also successfully live-migrated virtual machines from one host to
another.

We started experimenting with gfapi and saw a big improvement of
I/O-performance, however, live-migration is not working the way we hoped.

Live-migration itself is no problem at all, the problem is that we have to
define a specific host for gfapi to access the data on the volume as
opposed to using the fuse-client where that was not needed. Suppose we have
a virtual machine on machine A with machine A defined as its host for the
gfapi storage backend. When we migrate a virtual machine from machine A to
machine B, it will still use machine A (since it is defined that way in the
configuration) to access its virtual harddrive and therefore we cannot
remove machine A from the cluster without breaking the virtual machine.

We have tried defining a special hostname (other than localhost) that
resolves to the machine the virtual machine is running on, but that did not
work.

Ideally we should be able to migrate virtual machines from machine A to
machine B and be able to shutdown machine A without impacting the virtual
machine in any way.

Is there a solution or an acceptable workaround for this problem?

Thanks,
Stephan
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.gluster.org/pipermail/gluster-users/attachments/20150121/c3e8d556/attachment.html>