Defining backups and snapshots
From an OpenStack perspective, there are distinct differences between a backup and snapshot of an instance. Those differences could influence the use of each of those functions. Keep in mind that with keeping with true cloud behavior, all cloud resources are meant to be disposable. You may ask what that statement really means. It simply means that any instances or volumes (resources) created to support your application functions should be able to be recreated in some sort of automated fashion. Instilling the pets versus cattle analogy. No longer are the days of attempting to bring a sick VM back to life.
Destroy the instance, recreate it, and off you go again. These principles remove the want for instance backups. With this said, there will be cases where you may want to have a backup of an instance. So, let's first examine the capability of taking an instance backup.
The OpenStack Compute service (Nova) functionality of backing up an instance behaves just like...