Tiered Storage : Consolidation of Server Storage

If you look the category listing of this article, you will notice that, this article is neither sub categorized under Virtualization or Cloud Computing. The reason is, tiered storage, right now can be placed under both categories.
You probably have heard about Hierarchical storage management, Tiered Storage classically belongs to Hierarchical storage management (HSM). HSM is a data management system which moves data between higher cost Data storage system and lower cost storage system. A good example can be – 5 yrs old data of a Stock Exchange or Forex. The old data is is important and have to be archived for any reference but quite obviously it does need a High Availability Cloud Storage, that is right now that particular Stock Exchange is using. Tiered storage actually defines Price, Performance, Capacity and sometimes Function. We have given very crude example to explain both Tiered Storage and HSM, but probably it is enough to make you understand the concept of Tiered Storage.

Why the requirement of Tiered Storage is increasing

Its quite obvious, the amount of data and bandwidth we are using now, is probably 5 times more than 5 years back. From a webpage to an image – the size of any file is increasing and keep in mind, all these data is actually being gathered and piled up. The major advantage of a tiered storage architecture are :

• Tiered Storage is cost effective
• It is capable of saving the space
• Tiered Storage is energy efficient

Tiers of Tiered Storage

This is the actual flavor of Tiered Storage. Usually Tiered Storage is divided in to 4 classes –

Tier 0 : This is the top notch layer of Tiered Storage. High availability is ensured by using Enterprise Solid State Drives (ESSD).

Tier 1 : Usually SAS hard drives are used with high RPM to ensure the demand of data seeking.

Tier 2 : For lesser performance, lower RPM SAS drives are used.

Tier 3 : This is what we actually gave the example for Tiered Storage – this is for archiving information.

Now let us understand how Tiered Storage is important : Quite obviously, data suitable to Tier 3 can be stored on a ESSD – that is on Tier 0 of Tiered Storage as we have said. But the cost will increase.

Usage of Cloud Computing in Tiered Storage

Usage of cloud computing in Tiered Storage probably has not been implemented by any enterprise at the time of writing this article. There are definite advantages of using Cloud Computing in Tiered Storage. But there are certain limitations still now.