MCPc Blog

Data Storage Management Options

At the simplest level, data center managers have two choices when considering storage options:

• Do nothing and continue to buy more disk storage, or
• Implement some type of storage management solution to help control the seemingly unrelenting nature of storage growth. 

You may subscribe to the do-nothing approach and rationalize this decision because of the relatively low cost of disk storage. However, there are more expenses associated with adding storage than the initial capital expenditure. For example, consider the costs of real estate in the data center, the ongoing expense of power and cooling, and the added workload for IT staff. In addition, all disk storage will eventually need to be replaced — if for no other reason than age — and the more disks you replace, the greater the cost.

For these reasons, it is preferable to get a handle on storage proliferation and adopt a suitable data storage management solution. With managed storage, you can better control operating costs, maintenance needs and physical data center growth.

Prioritizing Your Data

The first step should be to get your “storage stakeholders” together. This group of people may include:

• Line-of-business managers
• IT directors
• Department heads
• Storage administrators
• C-level executives
• Legal advisors
• Anyone else involved in making decisions about storage retention and access

At a high level, everyone should try to reach a consensus about how to categorize the company’s data. Though every organization is different, essentially you’ll want to prioritize your data in the following categories:

• Priority 1: Data critical to daily operations
• Priority 2: Less critical data that still needs to readily accessible
• Priority 3: Data that can be archived for potential access at some point in the future
• Priority 4: Data that can be deleted

These priorities correlate directly to the type of storage media that the data will be stored upon. For this reason, keep in mind that depending upon your industry there may be legal guidelines that dictate certain data policies and data retrieval abilities.

Once you have categorized your data and established a corresponding data storage retention and access policy, it is time to start investigating potential storage solutions. A common approach is to assign each data priority level to a storage tier.

Standard Data Storage Tiers

Fibre-Channel Drive

Tier 1 

Typically your fastest and most reliable disk array(s). This is the electronic warehouse for Priority 1 data — data that is most frequently accessed and deemed most important to daily business operations.  It is most common to see the highest performance, and therefore most expensive, SAS or Fibre-Channel based disks used at this top level.

Tier 2

This tier is usually comprised of larger capacity spinning disks that are not quite as fast as the disks used in Tier 1, and is suitable for Priority 2 data. Often SATA disks are used for Tier 2 storage. Keep in mind, however, that SATA disk drives vary greatly in quality. Some manufactures use terms like enterprise-class SATA and other marketing speak, but the best indication of quality designation is the warranty of the drive. Therefore, be certain to check and compare warranties.

Tier 3 

A tape drive, autoloader or library is most commonly used for Priority 3 data archive or backup.  You could refer to this as long-term storage. Some tape libraries are left online, allowing end-user access to the data that is stored on the tape. Even if the data an end user requires is offline, some storage management software will indicate this and alert the administrator to load the appropriate tape cartridge. Optical disc drives and libraries can also be used at this tier, although they are not as popular as they once were.

Tier 4

This is the bit bucket, or the trash, and ideal for Priority 4 data. Inevitably, there will be data that is deemed unworthy of preservation — personal mp3 files on end-user computers that policy recognizes as inappropriate, for example. Consequently, the files are transitioned to never-never land. Some organizations are prohibited from deleting any files, however, and therefore Tier 4 storage would not be a valid target option.

Tier 0

This is a fairly new tier, created predominantly because of the availability of Solid State Disks (SSD) of either the DRAM or NAND Flash varieties. SSD usage is largely relegated to special usage, such as for video-streaming applications and disk-backup appliances, which utilize SSDs for meta-data operations. However, many people (me included) believe that SSDs will continue to encroach upon the dominance of traditional spinning disk, as improvements to the technology continue to be made. Already, SSDs offer greatly improved performance and consume far less power than spinning disk, which translates into greatly reduced heat generation and lower operating costs.

Data Tiers and Hierarchical Storage Management

To streamline your data management further, you can implement HSM (Hierarchical Storage Management) software. This solution allows you to set automated storage policy controls based on a set of established file criteria, considering information such as:

• File size
• Age of file
• Type of file
• File ownership
• Date of last access
• Combination of the above

By considering how these criteria apply to different data priority levels, you can easily get your data to the appropriate storage tier with minimal ongoing management. The process runs on a server or a dedicated appliance. Once the file criteria have been met, the file is automatically moved to a particular storage location based upon your set policies. End-user access to the file can be maintained via stub files and pointers, although access may be slower if the file has been relocated to tape, for example.

With HSM software, you can allow end users to access stored files as if nothing has changed, even after they have been relocated.

Summary

If you are constantly adding more storage to accommodate data growth, you may want to consider a storage management solution like one of the above. Meet with key decision makers and storage stakeholders to talk about categorization of your data. Discuss what data retention policies should look like, as well as ongoing access to data. Remember to check legal implications if they apply. Finally, engage a trusted business advisor with storage management expertise to help you sort through the many available products in the marketplace and select the best solution for your requirements.

 

Perry Szarka is a Solution Consultant at MCPc with expertise in data storage and network infrastructure. He works closely with clients to understand their business objectives and discover solutions to help them achieve their goals.

Image Credits:

http://upload.wikimedia.org/wikipedia/commons/d/de/Fc-disk.jpg

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