[NetApp] catch errors on getting vserver when reusing share server

fixes e.g. 'Vserver name is absent in backend details'

Closes-Bug: #1993829
Change-Id: I94b2576d808967517733bdcbb81444290e31b518

manila/share/drivers/netapp/dataontap/cluster_mode/lib_multi_svm.py

@@ -896,8 +896,16 @@ class NetAppCmodeMultiSVMFileStorageLibrary(
 
         backend_name = share_utils.extract_host(share_server['host'],
                                                 level='backend_name')
-        vserver_name, client = self._get_vserver(share_server,
-                                                 backend_name=backend_name)
+        try:
+            vserver_name, client = self._get_vserver(share_server,
+                                                     backend_name=backend_name)
+        except (exception.InvalidInput,
+                exception.VserverNotSpecified,
+                exception.VserverNotFound) as error:
+            LOG.warning("Could not determine vserver for reuse of "
+                        "share server. Share server: %(ss)s - Error: %(err)s",
+                        {'ss': share_server, 'err': error})
+            return False
         vserver_info = client.get_vserver_info(vserver_name)
         if (vserver_info.get('operational_state') != 'running'
                 or vserver_info.get('state') != 'running'

releasenotes/notes/bug-1993829-netapp-guard-vserver-name-c65ab9e811b398a8.yaml

@@ -0,0 +1,6 @@
+---
+fixes:
+  - |
+    NetApp driver: Added a guard on getting share server backend detail vserver
+    name when trying to reuse share server. Please refer to
+    `Launchpad Bug #1993829 <https://bugs.launchpad.net/manila/+bug/1993829>`_.