[Users] VM migrations failing

[Dan Kenigsberg]

On Fri, Feb 01, 2013 at 11:44:08PM +0100, Martin Kletzander wrote:
> On 02/01/2013 09:29 PM, Dead Horse wrote:
> > To test further I loaded up two more identical servers with EL 6.3 and the
> > same package versions originally indicated. The difference here is that I
> > did not turn these into ovirt nodes. EG: installing VDSM.
> > 
> > - All configurations were left at defaults on both servers
> > - iptables and selinux disabled on both servers
> > - verified full connectivty between both servers
> > - setup ssh (/root/authorized keys) between the servers --> this turned out
> > to be the key!
> > 
> > Then using syntax found here:
> > http://libvirt.org/migration.html#flowpeer2peer
> > EG: From the source server I issued the following:
> >
> 
> So your client equals to the source server, that makes us sure that the
> connection is made on the same network for p2p and non-p2p migration.
> 
> > virsh migrate --p2p sl63 qemu+ssh://192.168.1.2/system
> > 
> 
> You're using ssh transport here, but isn't vdsm using tcp or tls?

It is!

> According to the config file tcp transport is enabled with no
> authentication whatsoever...
> 
> > It fails in exactly the same way as previously indicated when the
> > destination server does not have an ssh rsa pub ID from the source system
> > in it's /root/.ssh/authorized_keys file.
> > However once the ssh rsa pub ID is in place on the destination system all
> > is well and migrations work as expected.
> > 
> 
> ..., which would mean you need no ssh keys when migrating using tcp
> transport instead.
> 
> Also during p2p migration the source libvirt daemon can't ask you for
> the password, but when not using p2p the client is connecting to the
> destination, thus being able to ask for the password and/or use
> different ssh keys.
> 
> But it looks like none of this has anything to do with the problem as:
> 
>  1) as you found out, changing vdsm versions makes the problem go
> away/appear and

I've missed this point. Which version of vdsm makes it go away?

> 
>  2) IIUC the first error was "function is not supported by the
> connection driver: virDomainMigrateToURI2", but the second one was
> "error: operation failed: Failed to connect to remote libvirt URI".
> 
> Since I tried finding out why the first error appeared, I probably
> misunderstood somewhere in the middle of this thread and am useless
> here.  However if I can help from the libvirt POV, I'll follow up this
> thread and will see whether there's anything related.