A new approach to protecting data: Time Addressable Storage - Storage Networking

Computer Technology Review, Dec, 2003 by Kirby Wadsworth

Forget backup. For nearly five decades, the data storage industry has been focused on the wrong issue. Making, storing, and managing frozen copies of data is a futile waste of time, energy and money. Everyone knows it, so I'll be courageous enough to say it--backup sucks! It literally sucks time, resources and incredible amounts of money out of the IT budget. And, the truly frightening reality (in this age of enlightened ROI) is that backup adds no value to a business enterprise--none, nada, zilch.

Forget Restore

Since backup is so bad, it has now become fashionable in IT cognoscenti circles to say we are focusing on restore--not backup. This deflects the focus from our futile efforts at making single-point-in-time (SPIT) copies to the more acceptable effort of actually restoring and recovering from data loss. After all, isn't our ability to restore really what all this data protection buzz is really all about anyway? Unfortunately, restoring data from last night's backup won't get your applications back on line fast enough--too much data has changed in the last two hours. Heck, too much has changed in the last two minutes! No, it's not all about restore either ...

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Time is Money ... and You Don't Have Enough of Either to Waste Time with SPIT

Regardless of how you make and store backups--disk to disk, disk to tape, disk to disk to tape, disk to disk to disk(!?)--if you rely on SPIT images as the core of your data protection strategy, you face a multitude of problems when bad stuff happens to your data--and we all know, bad stuff will happen.

If your data protection strategy centers on performing standard backups at midnight--and statistically it probably does--then you're risking up to 24 hours of data loss. If you're among the few who use periodic snapshots or mirror-splits, your risk of losing 6 to 12 hours of data is still very real.

One solution might be to make more copies, more frequently. So, instead of daily back- ups, you might back up every 4 or 6 hours, creating a smaller window of potential loss. Traditional single-point-in-time backups take hours and, in many instances, critical business applications are offline or severely impacted during this "backup window." You might try to snap a SPIT of your data every fifteen minutes using one of the newer generations of snapshot solutions. But, what a nightmare! Imagine the complexity and cost of making and managing over 100 copies of your data everyday. Who has time?

Sure, you understand the very real danger of data loss, but you have to weigh that risk against the cost of making and managing SPIT images.

In the end, creating and storing single-point-in-time images costs U.S. businesses billions of dollars in both downtime and hard costs, including thousands of expendable tape cartridges each year. And, we are still left with high degrees of risk.

Time Addressable Storage

Time Addressable Storage (TAS) is a new class of storage that instantly recreates data exactly as it existed at any previous point in time, ensuring rapid application recovery and timely resumption of business critical operations. And, the process of protecting data with TAS technology doesn't impact availability or performance. You don't take your applications offline, or put your databases into "backup mode" to ensure continuous protection. Further, TAS systems don't require frequent operational intervention--it's set and forget. TAS systems use storage media very efficiently, and they are completely non-disruptive to the current online environment. In short, they are a data protection dream come true.

Here's why. Traditional disk storage operates only in the present tense--when you write to a traditional disk, previous data is overwritten. You can only read what you last wrote. TAS adds time as a new dimension to storing data. Now, data can be accessed, as it existed at an exact moment in time. When asked to respond to a read or write request, the TAS system responds with data in its present state or just as easily with data as it existed two minutes ago, two seconds ago or two weeks ago.

The eventual proliferation of TAS devices will eliminate the proverbial backup window without the overhead and cost of multiple mirror sets or snapshots. In addition, because the presentation of time-stamped data is non-destructive, customers can recover an application quickly, without compromising the failure history, enabling--perhaps for the first time--after the crisis forensic analysis.

Time Addressable Storage--How practical is it?

TAS technologies have been developed to complement existing data protection technologies, dramatically reducing storage and recovery costs, simplifying the data protection process and reducing business risk. TAS doesn't require a rearchitecting the environment, or dramatically altering operations. Its offers a gradual, non-threatening approach--the more you use it, the more time and money it will save you.

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TAS is here today. At October's Storage Networking World conference, a panel of six continuous protection vendors--old school traditional vendors and emerging startups alike--convened to discuss approaches to delivering continuous protection systems. On the show floor even more vendors discussed and demonstrated continuous protection techniques. Most IT experts who get a firsthand view of TAS systems walk away impressed and excited. It's just so intuitive and so obvious that most just shake their heads and say, "Of course, why didn't we just do this in the first place?"