Hybrid Storage and Multiple Storage Tiers

One pressing challenge for server administrators is how to deal with an endlessly growing volume of data. New data is generated every day. People send email messages; they create Microsoft Word documents and Excel spreadsheets. Almost everyone that sits down at a computer in an office environment each day generates data in some way.

In most organizations, how that data is accessed changes over time. Newly generated files are accessed the most frequently. This access might be by the person who created the data, or it might be by many people. In most cases, the data is stored on a file server as that allows other people to access the data and provides a central location from where the data can be backed up.

As the file ages, it is likely to be accessed less frequently. For example, a spreadsheet describing an organization’s sales figures for a particular month will be accessed frequently in the months after its creation but is less likely to be accessed several years after after its creation. For the most part, files are accessed with decreasing frequency until they reach a point at which they become “dormant”—unlikely to be accessed again.

Although a systems administrator who needs to manage storage can be reasonably certain that a file that has not been accessed for 2 years will not be accessed again, you can never be 100-percent certain that this will be the case. This leaves you with a conundrum as to what to do with the data: Leave it in a place that is accessible to users who might need it, or move it to an offline location from which it must be manually retrieved?

For example, suppose your organization backs up data that hasn’t been accessed for a specific amount of time to tape, and then removes the data from those storage locations that users can access directly. Unless users are aware of this strategy, those who try to access dormant data might simply assume that it’s been deleted and is no longer available. Even if users are aware of the strategy, someone in the IT department will need to spend time tracking down the appropriate tape to restore so that users can gain access to the files they need.

This is where a device such as Microsoft StorSimple can provide an easy-to-implement solution for managing data: frequently used, infrequently used, and dormant. StorSimple is configured to keep frequently accessed data on a fast, local storage tier; to move less frequently accessed data out to traditional spinning disk; and to eventually move dormant data to the cloud.

The cloud turns out to be an excellent place to store dormant data. It has the benefit of being a low-cost solution while also providing functionally inexhaustible capacity. Each storage tier—be it an on-premises solid state disk (SSD) or magnetic disks of the StorSimple device or the tier hosted in Windows Azure—is redundant, ensuring that even dormant data is protected if storage fails. The same certainly can’t be said for dormant data stored on tape, which is only a tape failure away from being irrecoverable.

Another option is to mix technology Windows Server 2012 and Windows Server 2012 Storage Spaces with server OS features such as File Server Resource Manager. You can configure File Management Tasks in File Server Resource Manager to automatically move data that has not been accessed for a specific amount of time from file servers in on-premises locations to alternate locations. These locations can be file servers hosted in Windows Azure, which are connected to the local network through a site-to-site VPN.

In both scenarios, dormant data is automatically moved from an on-premises location to a location in the cloud, where it remains accessible should access be needed. The StorSimple solution is more straightforward to implement, as it has built-in redundancy and is configured to automatically move dormant data out to the cloud storage tier. A solution involving Storage Spaces, a site-to-site VPN, and file servers hosted in Windows Azure requires more configuration but might be better suited to meet specific organizational requirements. To find out more, visit Enterprise Storage at http://www.microsoft.com/en-us/server-cloud/solutions/storage.aspx.