I am reading up on Storage for Windows Server 2012 R2 and I am trying to understand the purpose of Storage Pools. The way they make it sound is that you can create one big expandable ever growing array of disk like a JBOD but with the difference of the ability to create volumes on top of those disks?
Is that correct thinking?
Although the concept is similar (take a bunch of disks and act like it's one storage device), they actually function on a different level. JBOD runs close to the hardware, often as part of a disk controller configuration. Microsoft's storage pools run on the OS level.
To illustrate this point: suppose you have a server with JBOD configured on the RAID controller. You can run any OS on that bunch of disks and every OS will happily communicate with that bunch, as long as the controller is supported by that OS. On the other hand, if you configure those disks as a storage pool, only Microsoft Windows will know what to do with it and other OS's can't use that storage pool.
Also see this Microsoft TechNet blog.
Not even reliable solutions have their uses.
If availability is more important in your case, you should pay a look at other types of Raid.
If you prefer, you can make out the probability of failure of the Raid.
But remember, do not Raid for reliability and storage of data, and to increase accessibility.
The term JBOD is often used to describe a collection of disks connected to a non-RAID controller. However, that is incorrect. JBOD is a method of storing data on a collection of those disks.
Storage Spaces is another method of storing data on disks. The disks that Storage Spaces control are called the Storage Pool.