Enable pushgateway persistent storage

Change-Id: Ic850cadd55b842c784d9271dc62cc46b389604a1
Closes-bug: PROD-21073
diff --git a/prometheus/pushgateway/container.yml b/prometheus/pushgateway/container.yml
index d0e986e..e4e9cd7 100644
--- a/prometheus/pushgateway/container.yml
+++ b/prometheus/pushgateway/container.yml
@@ -1,2 +1,3 @@
 classes:
 - service.prometheus.pushgateway.container
+- system.prometheus.pushgateway
diff --git a/prometheus/pushgateway/init.yml b/prometheus/pushgateway/init.yml
new file mode 100644
index 0000000..a906807
--- /dev/null
+++ b/prometheus/pushgateway/init.yml
@@ -0,0 +1,7 @@
+parameters:
+  _param:
+    prometheus_pushgateway_data_directory: /opt/pushgateway/data
+  prometheus:
+    pushgateway:
+      dir:
+        data: /srv/volumes/local/pushgateway/data