[lxc-users] Migrating LXD VMs/containers between nodes

[Tycho Andersen]

On Thu, Nov 26, 2015 at 09:50:59AM -0200, Dilvan Moreira wrote:
> On Wed, Nov 25, 2015 at 3:50 PM, Serge Hallyn <serge.hallyn at ubuntu.com>
> > The biggest complication I see is that when you ask lxd to move a
> > container,
> > lxd will want to migrate the rootfs.  I'm waiting for clarification from
> > Tycho on whether lxd will be smart enough to DTRT.
> >
> 
>    Using Ceph/rbd, there is no need to migrate anything. I am not aiming to
> have live migration, so the plan is to shutdown the container and start it
> agin in another node.

Migrating containers live or non-live uses the same filesystem backing
code to do it, since it needs to migrate the filesystem in both cases.
I have a branch that makes smarter per-backend decisions when you are
using a filesystem like ZFS or BTRFS, but it still has some bugs that
need to be worked out and I haven't gotten much time to work on it
recently.

We don't have a ceph (or block) backend today, so as Serge says there
is no way for LXD to understand that it shouldn't try to move the FS
today. I think we'd be happy to accept such a backend as a patch,
though :)

Tycho