Merge "Handle kolla-build exception"

kolla/cmd/build.py

@@ -73,8 +73,13 @@ class KollaRpmSetupUnknownConfig(Exception):
 
 
 def docker_client():
+    try:
         docker_kwargs = docker.utils.kwargs_from_env()
         return docker.Client(version='auto', **docker_kwargs)
+    except docker.errors.DockerException:
+        LOG.exception('Can not communicate with docker service.'
+                      'Please check docker service is running without errors')
+        sys.exit(1)
 
 
 class PushThread(threading.Thread):