Merge ~newell-jensen/maas:2.3-lp1741165 into maas:2.3

[Newell Jensen]

Backport of c5a810187578776c9dacf386d2628f23678a6aa2

LP: #1741165 -- Remove --delete-snapshots flag to workaround volumes not being deleted for node decomposition.

[Newell Jensen (newell-jensen)]

Self approved backport.

review: Approve

diff --git a/src/provisioningserver/drivers/pod/tests/test_virsh.py b/src/provisioningserver/drivers/pod/tests/test_virsh.py
index c6a0247..473bc60 100644
--- a/src/provisioningserver/drivers/pod/tests/test_virsh.py
+++ b/src/provisioningserver/drivers/pod/tests/test_virsh.py
@@ -1,4 +1,4 @@
-# Copyright 2017 Canonical Ltd.  This software is licensed under the
+# Copyright 2017-2018 Canonical Ltd.  This software is licensed under the
 # GNU Affero General Public License version 3 (see the file LICENSE).
 
 """Tests for `provisioningserver.drivers.pod.virsh`."""
@@ -1032,7 +1032,6 @@ class TestVirshSSH(MAASTestCase):
             call([
                 'undefine', domain,
                 '--remove-all-storage',
-                '--delete-snapshots',
                 '--managed-save'])))
 
 
diff --git a/src/provisioningserver/drivers/pod/virsh.py b/src/provisioningserver/drivers/pod/virsh.py
index a9b6775..e2de820 100644
--- a/src/provisioningserver/drivers/pod/virsh.py
+++ b/src/provisioningserver/drivers/pod/virsh.py
@@ -1,4 +1,4 @@
-# Copyright 2017 Canonical Ltd.  This software is licensed under the
+# Copyright 2017-2018 Canonical Ltd.  This software is licensed under the
 # GNU Affero General Public License version 3 (see the file LICENSE).
 
 """Virsh pod driver."""
@@ -771,9 +771,11 @@ class VirshSSH(pexpect.spawn):
         # Ensure that its destroyed first.
         self.run(['destroy', domain])
         # Undefine the domains and remove all storage and snapshots.
+        # XXX newell 2018-02-25 bug=1741165
+        # Removed the --delete-snapshots flag to workaround the volumes not
+        # being deleted.  See the bug for more details.
         self.run([
-            'undefine', domain,
-            '--remove-all-storage', '--delete-snapshots', '--managed-save'])
+            'undefine', domain, '--remove-all-storage', '--managed-save'])
 
 
 class VirshPodDriver(PodDriver):