Dec 27 2010

Managing Virtualized Storage

Virtual environments offer a lot of advantages, including lower cost and much higher utilization. However, riding herd on a group of virtual machines and servers requires a different approach than managing the equivalent amount of physical storage.

Here are some guidelines to help you get a handle on managing storage in a virtual environment.

Tip 1: Use a specialized tool. While managing storage using standard storage management tools is quite possible, it's harder and less transparent than with tools designed specifically for managing storage in the virtual world, and utilization is not as efficient.

Fortunately, there's a wide array of choices today. Companies such as virtualization manufacturer VMware and storage management and security manufacturer Symantec offer features and tools to help allocate, monitor and manage storage.

Tip 2: Use policy-based management wherever possible. One challenge with virtualized storage is that there’s so much of it. Every virtual machine has its own storage with its own logical unit number, for example. The best way to handle this is to set policies to cover most situations and apply them automatically across the various servers and virtual machines.

The idea is to reduce the amount of manual work to an absolute minimum by automating as much as possible. A well-thought-out series of policies can help cut down on the grunt work.

Tip 3: Develop a “gold copy” standardized stack. All your virtual machines should be identical when first created and then customized as needed. Set up a master or “gold” copy of your virtualized machine with all the appropriate utilities and applications that you need on your machines. Once you do that, it will take only a few minutes to clone the stack when a new virtual machine is required.

Because most organizations need a variety of machine configurations, it’s often difficult to hone it down to a single, one-size-fits-all machine or server. However, it’s realistic to expect that you can reduce your inventory to a few basic configurations that you can replicate and customize. This standardization is especially important when it comes to making sure all your machines and servers have the appropriate antivirus and other security protections installed.

Tip 4: Look for deduplication opportunities. Storing a single instance of data or an application can reduce storage demands by 10 to 1 or more. The nature of server virtualization (multiple virtual servers being served by a single pool of storage) and the growing sophistication of deduplication make it a natural fit for virtualization.

Tip 5: Consider tiered storage. Tiered storage isn’t absolutely necessary for managing virtual storage, but virtualization offers an excellent opportunity to improve efficiency and cut costs by dividing your storage up into tiers and supporting each tier with the most cost-effective combination of storage and networking hardware.

The percentage of survey respondents reporting annual data growth rates in the 11% to 30% range

Source: ESG survey, based on 493 responses

Serving lower-priority storage needs with less-expensive storage and networking, such as SATA disks and iSCSI networks, can save considerable money. Because virtualization tends to consolidate storage resources, it makes sense to combine tiered storage with virtualization.

Tip 6: Control virtual server sprawl. One of the great advantages of virtualization is the ease with which a new server or virtual machine can be created. A few simple commands, and there’s a brand-new machine or server ready to support your latest project.

Unfortunately, if you’re not careful, those easily added servers and machines can become a big problem. Without proper planning, you’ll have a sprawling mass of virtualized hardware running without any clear direction.

It’s imperative to control your virtualized systems right from the beginning and keep control as you move along. You should have firm policies on who can create virtual servers and machines, an approval process to make sure the new data is really needed and a lifecycle policy that will let you dismantle virtual hardware when it is no longer needed.