Added a note to the backup etcd topic.

Author: EricPonvelle

modules/backup-etcd.adoc

@@ -43,6 +43,11 @@ sh-4.2# chroot /host
 
 . Run the `cluster-backup.sh` script and pass in the location to save the backup to.
 +
+[TIP]
+====
+The `cluster-backup.sh` script is maintained as a component of the etcd Cluster Operator and is a wrapper around the `etcdctl snapshot save` command.
+====
++
 [source,terminal]
 ----
 sh-4.4# /usr/local/bin/cluster-backup.sh /home/core/assets/backup