On Mon, Mar 02, 2020 at 09:17:27AM +0100, Michal Privoznik wrote: > Libvirt tries to forbid migration onto the same host and it does > that by checking if local and remote hostnames are the same and > whether local and remote UUIDs are the same. Well, the latter > makes sense but the former doesn't really because libvirtd can be > running inside an UTS namespace and hostnames can appear the same > on both sides of migration. On the other hand, host UUIDs are > unique, so rely on them when trying to prevent migration onto the > same host.
This check originates in commit 8654175c5b0c3db9e5f70907f102f0f900355d28 Author: Daniel P. Berrangé <berra...@redhat.com> Date: Mon Jan 24 18:06:16 2011 +0000 Introduce migration cookies to QEMU driver We've always had both hostname and uuid checks here, as a way to prevent localhost-migration. The only way I can think to bypass the UUID check is to run a second libvirtd on the same host, but inside a container so you can change UUID or libvirtd.conf. At that point, you can set things up so that you are safe todo a local migration, so its ok to allow for that. > Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1639596 > > Signed-off-by: Michal Privoznik <mpriv...@redhat.com> > --- > src/qemu/qemu_migration_cookie.c | 12 +++++------- > 1 file changed, 5 insertions(+), 7 deletions(-) Reviewed-by: Daniel P. Berrangé <berra...@redhat.com> Regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|