[libvirt] [PATCH 5/6] allow non-zero success values from a domain's MigratePerform

[Paolo Bonzini]

>    Sounds fine by me, but I wonder about the change of semantic for
>    client server not at the same version level. Could you explain what
> might happen in those case ?

Here is the result of my testing (source libvirtd is always new):

source virsh     source method      destination libvirtd      result
-----------------------------------------------------------------------
    old              qemu://                 old              runs (bad)
    old              qemu://                 new              runs (bad)
    old            qemu+tcp://               old              runs (bad)
    old            qemu+tcp://               new              runs (bad)
    new              qemu://                 old              runs (bad)
    new              qemu://                 new              paused (ok)
    new            qemu+tcp://               old              runs (bad)
    new            qemu+tcp://               new              paused (ok)

So you do need not just a new daemon, but also a new virsh to fix the 
bug.  However, the good news is that in no case the migration fails, 
even when using an old virsh and connecting to the daemon via a remote 
connection.

Paolo