Traditional backups simply copied the contents of a server or data center to tape. Nobody worried about what data was being copied or thought about its importance to the business, and strategies involved little more than just scheduling backup jobs and keeping track of tape rotation. But the role of backups is changing in today's enterprise, and this changing landscape demands far more thoughtful and comprehensive planning than in years past.
"Backup strategy is a plan, a focus, to ensure that you can recover data whether it's lost, deleted, or destroyed for whatever reason," says Greg Schulz, founder and senior analyst at Storage IO Group.
The biggest weakness with backups is that "strategy" is often confused with "tools." Analysts are quick to note that software and hardware certainly play central parts in any backup system, but the availability of tools does not guarantee a sound backup practice. For example, a virtual tape library (VTL) running from NetBackup doesn't mean that crucial data is being backed up adequately, or is even recoverable. A solid plan is needed to ensure that the tools are being utilized properly. Schulz compares this to building a house where the hammer, saws, nails and wood are used to follow the plan delineated in a blueprint. "Use the tools to implement the plan or facilitate the strategy," he says.
Answering the important questions
Storage administrators are realizing that there is simply too much data to back up and not all of that data is really essential to daily business operations. Administrators must sometimes perform data triage, allocating backup resources for only the most important applications. Backup strategies can help set a suitable RTO by allowing an enterprise to identify and prioritize mission-critical applications and determine how quickly those applications need to be recovered in an emergency.
Once an administrator understands that all applications and data are not created equal, it's no longer necessary to backup everything at the same time. Backup strategies can help set a suitable RPO by allowing businesses to determine a backup frequency and schedule for each data type.
An organization must identify the available backup window and select a technology, or multiple technologies, to achieve backup or restoration objectives. A backup strategy allows businesses to select the most appropriate backup technologies and determine the level of investment needed in those technologies. For example, organizations with mission-critical data may benefit from a continuous data protection (CDP) platform when backup windows and recovery objectives are smallest, but other organizations might select a virtual tape library (VTL) to leverage the performance of disk storage.
Retention is another important consideration that is often overlooked by traditional "all-or-nothing" backups. When you're able to identify the relative importance of data, it's possible to assign an appropriate retention period for each data type. A backup strategy can help to determine retention periods that meet regulatory requirements and business continuance needs for each data type. Retention needs may have an impact on storage platforms as well. For example, a health care provider might find that patient data may demand retention for 20 years and this may dictate the use of a content-addressed storage (CAS) platform.
Formulating the right plan
So how complex or detailed does a backup strategy need to be? There is no single answer to this question -- the "right" plan depends on your own organization and needs. A small environment may only need to backup work data to a conventional tape drive once a week. Other organizations might require a disk-based storage array to support periodic snapshots of important servers. Large firms might demand a continuous data protection (CDP) platform to continuously backup transactional data [see the SearchStorage.com article on CDP here]. The key is to understand what you need to backup, where the backup target should be, why the backup is taking place and then match the tools to suit those needs.
While a backup strategy can become quite complex, it generally does not detail specific pieces of equipment or software -- it simply doesn't require that level of granularity. "It's the high-level architectural standpoint," Preston says. "It's not the model of tape drive or the version of backup software that you're going to use." The real emphasis is to establish the direction that you want to follow.
Still, regardless of the detail and complexity involved in your own backup strategy, analysts emphasize the overriding idea of "recoverability" in any plan. Even the most comprehensive backup plan is useless without a close consideration of RPO and RTO. "The focus on the actual backup is sometimes more important," Schulz says. "But I think we're seeing more and more focus shifting toward the recovery -- how easy is it, and how quickly can you do it?"
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