Update VERSION and XOS parent container

Change-Id: I1520e63d0b399c6e0273123c3305fbe6058d88c6
diff --git a/Dockerfile.synchronizer b/Dockerfile.synchronizer
index eb62489..abc79f6 100644
--- a/Dockerfile.synchronizer
+++ b/Dockerfile.synchronizer
@@ -14,7 +14,7 @@
 
 # xosproject/openstack-synchronizer
 
-FROM xosproject/xos-synchronizer-base:2.0.0
+FROM xosproject/xos-synchronizer-base:2.1.9
 
 COPY xos/synchronizer /opt/xos/synchronizers/openstack
 COPY VERSION /opt/xos/synchronizers/openstack/