[libvirt-users] tunneled VM migration error

[Jiri Denemark]

On Wed, Mar 07, 2012 at 21:23:30 +0000, Shantanu Pavgi wrote:
> 
> I am getting following error with tunneled migration command: 
> {{{
> $ virsh --connect qemu:///system migrate --verbose --p2p --tunnelled 32 qemu+ssh://kvm-03/system
> error: operation failed: Failed to connect to remote libvirt URI qemu+ssh://kvm-03/system
> 
> }}}
> 
> However I am able to perform other virsh command like list, pool-list, dumpxml using the same remote libvirt URI: 
> {{{
> $ virsh --connect qemu+ssh://kvm-03/system list
> }}}
> 
> Also, the hypervisor native migration is working fine with following command:
> {{{
> $ virsh --connect qemu:///system migrate 31 qemu+ssh://kvm-03/system
> }}}
> 
> I am confused why remote URI worked for some of the commands but not for the
> migrate command. Am I missing something with the tunneled migration command
> or libvirtd/qemu configuration file? Any help would be appreciated.  

The thing is that for peer-to-peer migration (and tunnelled one is currently a
special case of it) the destination URI (qemu+ssh://kvm-03/system) is used by
the source libvirt deamon to connect to the destination deamon. In case of
normal migration or virsh connect, it is virsh, i.e., libvirt client, that
initiates the connection. And libvirtd has no way of asking you for a password
used when you ssh to kvm-03 nor does it have access to your ssh keys or
kerberos tickets. In other words, for p2p migration, you need to use different
transport than ssh.

Jirka