Enable kubernetes_metadata by default for ELK stack

cluster/addons/fluentd-elasticsearch/fluentd-es-image/Makefile

@@ -16,7 +16,7 @@
 
 PREFIX = gcr.io/google_containers
 IMAGE = fluentd-elasticsearch
-TAG = 1.20
+TAG = 1.21
 
 build:
 	docker build --pull -t $(PREFIX)/$(IMAGE):$(TAG) .

cluster/addons/fluentd-elasticsearch/fluentd-es-image/td-agent.conf

@@ -279,10 +279,9 @@
   tag cluster-autoscaler
 </source>
 
-# Uncomment in a case of daemon-set usage
-#<filter kubernetes.**>
-#  type kubernetes_metadata
-#</filter>
+<filter kubernetes.**>
+  type kubernetes_metadata
+</filter>
 
 <match **>
    type elasticsearch