commit d9311fffa36dfe12ac12f81c778c1c8d95e43c57
Author: Ke Wu <mikewu@google.com>
Date:   Tue Nov 8 15:26:32 2016 -0800

    metadata_watcher.py: avoid keeping trying to connnect to metadata service
    
    When ran on KVM, google-instance-setup.service (which is a oneshot
    agent) keeps trying to connect to the metadata service which is
    inaccessible during VM_Test of lakitu.  It makes
    google-instance-setup.service ends in an infinite loop and can't
    finish the setup. Skip the loop completely.

diff --git a/google_compute_engine/metadata_watcher.py b/google_compute_engine/metadata_watcher.py
index e7da49b..b85a15f 100644
--- a/google_compute_engine/metadata_watcher.py
+++ b/google_compute_engine/metadata_watcher.py
@@ -152,17 +152,13 @@ class MetadataWatcher(object):
     Returns:
       json, the deserialized contents of the metadata server.
     """
-    exception = None
     while True:
       try:
         return self._GetMetadataUpdate(
             metadata_key=metadata_key, recursive=recursive, wait=wait)
       except (httpclient.HTTPException, socket.error, urlerror.URLError) as e:
-        if isinstance(e, type(exception)):
-          continue
-        else:
-          exception = e
-          self.logger.exception('GET request error retrieving metadata.')
+        self.logger.exception('GET request error retrieving metadata. %s.', e)
+        break
 
   def WatchMetadata(self, handler, metadata_key='', recursive=True):
     """Watch for changes to the contents of the metadata server.