[libvirt-users] virt-manager/libvirt backwards compatibility problem?

[Whit Blauvelt]

Hi,

Wanting to test some recent features of libvirt, I installed 0.9.3 on a
couple of systems. It works fine on those, but since upgrading neither of
them can successfully connect with virt-manager or virsh to a couple of
other systems running libvirt 0.8.3. Even after upgrading virt-manager and
virtinst to the latest versions on the 0.9.3 systems, they fail like this
in virt-manager:

  Unable to open a connection to the libvirt management daemon.

  Libvirt URI is: qemu+ssh://root@192.168.1.67/system

  Verify that:
   - The 'libvirtd' daemon has been started

  Cannot recv data: : Connection reset by peer

  Traceback (most recent call last):
    File "/usr/src/virt-manager-0.8.7/src/virtManager/connection.py", line
  1055, in _try_open
      None], flags)
    File "/usr/local/lib/python2.7/dist-packages/libvirt.py", line 102, in
  openAuth
      if ret is None:raise libvirtError('virConnectOpenAuth() failed')
  libvirtError: Cannot recv data: : Connection reset by peer

Virsh simple fails with:

  error: Cannot recv data: : Connection reset by peer
  error: failed to connect to the hypervisor

Since it's certain that the libvirtd daemon has been started on the other
systems (they have production VMs that are running), this leaves me puzzled.
This connection for virt-manager worked flawlessly for months when all the
systems had libvirt 0.8.3.

Is this a known incompatibility? Something I have to tweak somewhere?

Thanks,
Whit