LTO-5 tape can't stop backup hardware trend toward disk

Heading into 2011, reports of the death of tape backup continue to be an exaggeration, and the emergence of faster and denser LTO-5 tape could spark an increase in interest in the age-old backup hardware medium. But the general consensus is that even LTO-5 won't stop the ongoing trend toward disk backup and data deduplication technology.

Last year saw larger, faster and more scalable disk-based hardware product updates hitting the market, typically with improved integration of backup software and support for Symantec Corp.'s OpenStorage Technology (OST) API. Declining reliance on the virtual tape library (VTL) interface also continued, according to a Storage magazine Purchasing Intentions survey.

"Organizations now want preconfigured, pre-tested solutions vs. trying to integrate their own," said Dave Russell, a research vice president at Gartner Inc. "The other trend is that the need for backup software to emulate tape has really diminished now. The backup software has gotten to the point where it understands disk."

NOTABLE BACKUP HARDWARE INNOVATIONS IN 2010

Symantec turned heads in September when it entered the hardware fray with the disk-based NetBackup 5000 appliance, capable of delivering both source and target deduplication. The appliance is a product of its joint venture with Huawei Technologies Co. Ltd., a telecom provider based in China.

"That was a big one. You're talking about the market-leading software-only company taking a left turn, and there's more to come," said Lauren Whitehouse, senior analyst at the Enterprise Strategy Group. She predicted that not only will Symantec up the ante but also that additional vendors will follow suit.

Additional hardware-software partnerships that have surfaced include the NetApp Syncsort Integrated Backup offering and Dell Inc.'s hardware with data deduplication via CommVault Systems Inc.'s Simpana, EMC Corp.'s Avamar and Symantec Corp.'s PureDisk.

"That's probably one of the biggest innovations that we've seen recently," said Rachel Dines, an analyst at Forrester Research Inc. The trend toward better integrated backup hardware and backup software, in turn, is having a major impact on implementation plans, she added.

"I've talked to quite a few end users who are really excited about this, because if you're going to be changing your backup software, a lot of the time, that goes hand and hand with changing your backup hardware," Dines said. "If you can just go to one place and get a pre-integrated hardware/software appliance that does everything, it can make deployment a lot faster and easier."

Historically, the appliance model has found favor primarily with small- and medium-sized businesses (SMBs) or in branch offices of large corporations, because the devices tend to have trouble scaling. Dines warned that the most of the current crop of appliances aren't scalable enough for enterprise data centers, but she expects that to start to change during the next few years.

UNIVERSITY CHOOSES EMC AVAMAR AS IT PHASES OUT TAPE

Temple University chose a preconfigured version of Avamar installed on EMC Corp. hardware when it embarked on the first phase of a long-term strategy to eliminate tape. Stan Horwitz, a senior systems manager at the Philadelphia school, said he wanted to be able to point to a single vendor in the event of a problem and ease system management. He also liked its integration with the EMC NetWorker backup software that Temple has used for years.

But, equally important, Avamar held out the promise of scale, with global and Source deduplication capabilities. Temple has identity management and other clustered servers that have the same data but are separated only for load balancing reasons. "Why invest in capacity to back up the same data twice?" said Horwitz.

Temple is currently using 82.8% of Avamar's 32.7 TB of available raw disk capacity to protect 47.6 TB of compressed data, which would rehydrate to 1.4 PB in an uncompressed state, according to Horwitz.

"Ultimately, the goal is to have everything on Avamar and do some off-site disk replication, but we're not at that point yet," said Horwitz.

In October, 275 application servers relied on Avamar for backups, and 168 application servers used tape. Data from some systems, such as ERP and Web servers, goes to Avamar and to tape. Other data, such as the school's 2 TB of Exchange Server data, uses only disk because backing up to tape would take too long.

"We're still figuring out the balance of what goes on tape and what goes on Avamar," said Horwitz. "Business-critical data goes on Avamar; anything that's not goes on tape."

Temple's LTO-3 tape has reached its end of life, and the school is currently debating an investment in LTO-5. But, Horwitz said even LTO-5 would never match the convenience of disk. "Users can do restores off Avamar whenever they want," he said.

TAPE BACKUP IS STILL ALIVE

This fall's Storage magazine Purchasing Intention survey of 317 IT professionals involved in the purchase of backup and disaster recovery products showed that 76% see their use of tape as a backup format either declining or staying the same.

LTO-5 was major innovation ... however, the usage and implications of that are yet to be seen.

 

Arun Taneja
founder and senior analystTaneja Group

But, that's not to say that tape has no future, since 22% said their use of tape had increased or would increase in 2010. Among 127 IT pros who purchased or planned to purchase tape libraries this year, 35% indicated they would go with LTO-4, and 21% favored the next-generation LTO-5.

LTO-5 nearly doubled the capacity of its predecessor LTO-4, from a native capacity of 800 GB to 1.5 TB, and the data transfer rate increased from 120 MBps to 140 MBps. It also includes a partition feature that enables tape to be divided into two separate writable areas. IBM's release of a Long Term File System (LTFS) for LTO-5 tape libraries holds out the potential of improved searching and indexing of data.

"LTO-5 was major innovation, particularly in conjunction with the file system. However, the usage and implications of that are yet to be seen," said Arun Taneja, founder and consulting analyst at Taneja Group, noting that beyond announcements, little has emerged.

Dines said LTO-5 triggered a bit of excitement about tape from "people who hadn't really been excited about it in a while." But, she added, "I'm not going to lie and say that LTO-5 means that lots more people are adopting tape. I still think tape is on the decline overall."

REMOVABLE DISK DRIVES AS AN ALTERNATIVE TO TAPE

Take Larry Walker, vice president and data processing officer at Chelsea Groton Bank in Groton, Conn. He said he loves his LTO-4 tapes compared to what the bank used in the past. But, now that the price of disk has dropped, he would prefer to shift to removable hard disk drives rather that upgrade to LTO-5 at some point in the future, if the bank's regulators and auditors approve.

"I don't think that tapes can do it anymore. We have too much data," Walker said. "They double the size of tape every two years, but the data doubles right along with it."

An online survey of 510 IT professionals responsible for data protection, conducted this year by ESG, showed that an average of 36% of backup data was stored on internal servers, 30% on tape, 28% on external disk-based storage systems, and 6% on off-site third-party service provider's storage.

But, by 2012, the IT pros signaled that tape will drop to 24% and internal server storage to 33%, while external disk-based storage increases to 33% and off-site third-party storage to 10%, according to the ESG survey.

MIXING IT UP: USING A COMBINATION OF DISK AND TAPE

A combination of tape and disk remain part of the backup strategy for many IT organizations, some of which continue to prefer the VTL approach, even when they opt for disk.

"It's preference," said Fred Gordon, a storage administrator at Farm Credit Services of Mid-America. "Just going straight to the disk works fine. But for me, it made more sense to mimic what we had out there already, because we've used a tape library before. It actually helped when moving over to this system from our old tape library. It wasn't as extreme as it would have been redoing our jobs in CommVault and going and sending everything to disk."

When we first implemented this project, we were all set to eliminate tape totally.

 

Fred Gordon
storage administratorFarm Credit Services of Mid-America

In March, Farm Credit Services made Spectra Logic Corp.'s nTier500 VTL-based disk system its primary backup device. SAN data had soared from 4 TB to more than 40 TB in three and a half years, and the storage team had been pushing the limits of its backup window with AIT-4 tapes.

But, the company didn't eliminate tape entirely. The IT staff also brought in a new LTO-4 tape system as a "fourth tier," because the company's retention policies require it to keep some records for at least seven years. LTO tape also enabled the company to encrypt data before sending it off-site.

"When we first implemented this project, we were all set to eliminate tape totally," said Gordon. "But, after doing the numbers and seeing how much we back up and what we had to do according to our policies, it made more sense in the end to go this route."

The company now replicates data between its production site in Louisville, Ky., and its disaster recovery facility in St. Paul, Minn., with its nTier500 appliances, which can store 26 TB at each of the two sites. Full backups are about 5 TB on Friday with differentials throughout the week. Farm Credit also uses Dell PowerVault MD3000i iSCSI boxes as a backup target for some non-critical data.

Under the new set-up, restores that once could take 24 hours from the disaster recovery site can be done in minutes. Farm Credit also saved about $12,000 in off-site tape storage costs, between the benefits of replication and dropping from 25 to 27 AIT-4 tapes to three LTO-4 tapes, according to Gordon.

"I have to be able to recover data, and from that standpoint, it was a great decision. From the standpoint of ease of use, another great decision," Gordon said.