Connecting to KVM does not support using ssh keys

[Frode Nordahl]

# snap info maas
[ snip ]
installed: 2.7.0-8135-g.321fadfe8 (4649) 130MB -

Adding KVM to a snap installed MAAS does not appear to work, example address: 'qemu+ssh://maas@10.219.3.1/system'

Excerpt from /var/snap/maas/common/log/rackd.log:
2019-11-13 09:15:20 provisioningserver.rpc.pods: [critical] Failed to discover pod.
 Traceback (most recent call last):
   File "/snap/maas/4649/usr/lib/python3/dist-packages/twisted/internet/defer.py", line 500, in errback
     self._startRunCallbacks(fail)
   File "/snap/maas/4649/usr/lib/python3/dist-packages/twisted/internet/defer.py", line 567, in _startRunCallbacks
     self._runCallbacks()
   File "/snap/maas/4649/usr/lib/python3/dist-packages/twisted/internet/defer.py", line 653, in _runCallbacks
     current.result = callback(current.result, *args, **kw)
   File "/snap/maas/4649/usr/lib/python3/dist-packages/twisted/internet/defer.py", line 1442, in gotResult
     _inlineCallbacks(r, g, deferred)
 --- <exception caught here> ---
   File "/snap/maas/4649/usr/lib/python3/dist-packages/twisted/internet/defer.py", line 1384, in _inlineCallbacks
     result = result.throwExceptionIntoGenerator(g)
   File "/snap/maas/4649/usr/lib/python3/dist-packages/twisted/python/failure.py", line 408, in throwExceptionIntoGenerator
     return g.throw(self.type, self.value, self.tb)
   File "/snap/maas/4649/lib/python3.6/site-packages/provisioningserver/drivers/pod/virsh.py", line 1398, in discover
     conn = yield self.get_virsh_connection(context)
   File "/snap/maas/4649/usr/lib/python3/dist-packages/twisted/internet/defer.py", line 1386, in _inlineCallbacks
     result = g.send(result)
   File "/snap/maas/4649/lib/python3.6/site-packages/provisioningserver/drivers/pod/virsh.py", line 1389, in get_virsh_connection
     raise VirshError("Failed to login to virsh console.")
 provisioningserver.drivers.pod.virsh.VirshError: Failed to login to virsh console.

This happens if no ssh password is provided, as ssh keys are currently not supported in the snap

[Alberto Donato (ack)]

Hi, are you specifying a password for ssh?

[Frode Nordahl (fnordahl)]

No, I would want it to use SSH key based authentication.

[Alberto Donato (ack)]

currently the snap only supports password authentication for ssh. This is probably why it's failing for you (the message could be more explcit about it but that's what we get from virsh)

[Alberto Donato (ack)]

With the change from the linked branch, ssh keys can be placed in /var/snap/maas/current/root/.ssh