Blade Systems Alliance Applied Systems & Interop Research Lab (ASIRL) BSA/National University

Better Backups

Christian Perry, Processor.com

2/4/2010

[Editor's Note: As digital narrows the data center technology gap, evaluate true disk vs. tape based storage ROI.]

Reconsider Your Backups & Long-Term Storage For Opportunities To Correct & Improve

Key Points

• Because backup systems aren’t always designed to handle long-term storage, it’s important to examine options for both backup and long-term storage to prevent sacrifices caused by using one or the other for both needs.

• In the presence of limited IT resources, deduplication can be an effective means of optimizing backups and restores, saving money, and cutting back on management requirements.

• Although tape-based systems might appear to be most cost-effective for backup and long-term storage, the technology contains hidden costs not evident in disk-based storage.

Target Your Needs

Although your long-term storage infrastructure might appear to be running correctly and adequately meeting the needs of your data center, it’s difficult to confirm its true state without testing. Kelly Lipp, chief technology officer of STORServer (www.storserver.com), notes that in many cases, testing can reveal that long-term storage systems are actually not functioning as expected, particularly when technologies originally designed for separate uses are mixed.

“Then, they must be augmented or replaced to ensure that they do,” Lipp says. “In these days of heightened scrutiny by regulating agencies, it is imperative that organizations know, rather than assume, these systems are indeed functional. If, on the other hand, they do function as required, there may be economies to be applied. For instance, there may be more effective storage strategies, such as tape, that are more cost-effective, green, reliable, and scalable than the existing technology.”

In most small to midsized enterprises, Lipp adds, backup software is also used to provide long-term storage. However, backup technologies aren’t necessarily designed to handle long-term storage requirements. With this in mind, Lipp recommends that data centers rethink their overall data protection requirements, because business requirements can suffer when using backup or archive technologies for both needs.

Take A Picture

Data snapshots aren’t a new concept, but the technology has evolved in recent years to become a viable alternative to other backup and long-term storage systems, says Bob Fine, director of product marketing at Compellent (www.compellent.com). In particular, data centers currently using incremental day-to-day backup and data recovery in their SANs could find value in snapshots, which capture only changed data in storage volumes rather than entire copies of volumes.

“With this flexibility, IT departments can quickly recover from a data loss by simply rolling back to a recent snapshot, which is by far faster and more effective than using tapes for backup,” Fine says. “Furthermore, snapshots also allow admins to test new applications without putting the production environment at risk.”

To extend this long-term storage concept, Fine suggests replicating snapshots to a secondary site for data protection. Data centers can potentially obtain true disaster recovery and manage data more effectively by replicating snapshots from one SAN to another rather than moving tape backups offsite.

Cut Back On Dupes

Smaller data centers that lack the IT resources of larger organizations can’t always enjoy the high-speed backup and restore performance and the resilient data protection that their larger counterparts can obtain. However, disk backup appliances that deploy deduplication technology can help to solve these problems, even without the presence of extensive IT staff and other resources.

“Deduplication is a system for replacing repeated data strings by pointers. It gives backup disk performance while reducing typical disk capacity requirements by 90% or more, and reducing disk needs means you can keep backup data around to use it for virtually all restores,” says Steve Whitner, product marketing manager at Quantum (www.quantum.com). “Applying deduplication to replication reduces the typical bandwidth needed to transmit data by a factor of 20 or more, allowing IT departments to back up data in remote offices to disk and to replicate the backup sets over a conventional WAN to a second office for DR protection.”

According to Whitner, many backup technologies, such as new tape drive technologies and deduplication, provide a measurable return on investment. Deduplication, in particular, can reduce acquisition and consumable costs by reducing the need for both spinning disks and removable media. There are also indirect gains involved with the technology, such as reduced time spent managing backups and reduced power, cooling, and space requirements for disk capacity that’s not deployed.

Beware Tape’s Hidden Costs

As the harsh economy continues to force data center managers to seek more budget-friendly technologies, tape backup seems like a no-brainer. But although tape media is inexpensive, there are hidden costs involved with using it, says Rob Walters, director of product management at The Planet (www.theplanet.com). In fact, it can be ultimately harder and costlier to manage than disk-based systems and result in a higher-than-anticipated TCO.

“To deliver any kind of data retention strategy, tapes must be packed and stored, which requires significant, error-prone manual labor,” Walters says. “Offsite storage means higher fees paid to a data storage provider as well as costs to transport the data to and from the data center. Additionally, while tape media itself has a life span of 30 years, newer-generation tape libraries are often not backwards-compatible, resulting in data migration challenges on a regular basis.”

Disk-based backups carry fewer maintenance costs than tape, he says, and they can be accessed quickly because they’re online. Further, there is no immediate risk of the technology becoming outdated, and new disk generations grow in capacity and decrease in cost. For true disaster recovery, Walters recommends not only disk-based storage but also moving those backups offsite, either to a third-party data storage provider or an online backup provider.

By: Christian Perry for .