Update backup.md (#3066)

docs/admin/vm-ops/backup.md

@@ -9,3 +9,12 @@ Best method of Janssen Backup is "VM Snapshot" backup. That means, backup / take
 
 Most platform virtualization software and cloud vendors have snapshot backup features. For instance, Digital Ocean has Live Snapshot and Droplet Snapshot; VMWare has Snapshot Manager, etc. 
 
+The Gluu Server should be backed up frequently--**we recommend at least one daily and one weekly backup of Gluu's data and/or VM**.
+
+It's also good to have some partial configuration backup as well. Such as: 
+
+ - Tarball `/opt`
+ - Tarball `/etc/jans`
+ - Tarball `/etc/apache2`
+ - Tarball `/var/jans`
+