Change default migration-auth-type from None to ssh

The default-auth-type only matters when enable-live-migration
is enabled, so we should make the default value something that
will deploy a functional cloud without requiring multiple
config values to be set

Change-Id: Icadf1ff7ce90a6a757d258c1f1dee70b8c1d6e0c
Closes-Bug: #1722456

config.yaml

@@ -127,7 +127,7 @@ options:
       compute hosts.
   migration-auth-type:
     type: string
-    default:
+    default: ssh
     description: |
       TCP authentication scheme for libvirt live migration. Available options
       include ssh.

hooks/nova_compute_context.py

@@ -182,10 +182,12 @@ class NovaComputeLibvirtContext(context.OSContextGenerator):
         if config('enable-live-migration'):
             ctxt['libvirtd_opts'] += ' -l'
 
-        if config('migration-auth-type') in ['none', 'None', 'ssh']:
+        if config('enable-live-migration') and \
+                config('migration-auth-type') in ['none', 'None', 'ssh']:
             ctxt['listen_tls'] = 0
 
-        if config('migration-auth-type') == 'ssh':
+        if config('enable-live-migration') and \
+                config('migration-auth-type') == 'ssh':
             # nova.conf
             ctxt['live_migration_uri'] = 'qemu+ssh://%s/system'
 

unit_tests/test_nova_compute_contexts.py

@@ -257,6 +257,7 @@ class NovaComputeContextTests(CharmTestCase):
              'kvm_hugepages': 0,
              'listen_tls': 0,
              'host_uuid': self.host_uuid,
+             'live_migration_uri': 'qemu+ssh://%s/system',
              'reserved_host_memory': 512}, libvirt())
 
     def test_libvirt_disk_cachemodes(self):