When Texas Tech University began to move away from relying solely on tape for backups, it found it easier and less expensive to add data deduplication licenses to its backup software than buying a dedicated deduplication hardware system.
Texas Tech's 28-person depart of Technology Operations and Systems Management (TOSM) handles centralized backups for the entire Lubbock, TX-based university system, which includes nearly 600 servers and more than 420 TB of data on Dell Inc./EMC Corp. Clariion and Symmetrix systems.
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TOSM assistant managing director Dustin Jordan says the university's data was growing about 1 TB a month, and it would run out of capacity on its Quantum Scalar i2000 tape library without an upgrade. So, last year he decided to switch to disk backup to reduce backup windows and facilitate remote replication to a new disaster recovery site Texas Tech will open before the end of this year.
"We offer free backups to anybody running a Windows or Linux server," Jordan said. "The project has funding through the Texas Tech CIO office, and it has been very popular. Even for people who do their own backups, we're considered the primary backup and they have their own backup for safety. We back up about 600 clients. On any given night, we back up about 10 terabytes.
"We were at the point where we were ingesting too much data. We were staring at serious tape infrastructure upgrades. We had two options: deduplication or upgrading our tape infrastructure."
TOSM looked at deduplication appliances from Data Domain and Quantum Corp., but Jordan realized he would need two large hardware systems to make replication work. Instead, Jordan said, the university could license the deduplication feature that its backup software vendor CommVault Systems Inc. offered in Simpana 8.
Texas Tech switched to CommVault from IBM Tivoli Storage Manager and Veritas NetBackup about six years ago. Jordan says he upgraded to CommVault's Simpana 8 as soon as it was available in March because of its new deduplication support.
"It all boiled down to costs," Jordan said. "With one of the hardware products, there was less flexibility to start with. You have a single point with deduplication, and everything files into to that. We also wanted to dedupe in the data center and replicate to the DR site."
He said to replicate with Data Domain or Quantum, he would've had to buy a second box for the DR site. "It was more expensive than the commodity storage that we could purchase for this [Simpana 8]," he said. "We already had disk storage for it. Data Domain did have a gateway that allowed you to use another vendor's storage behind it, but the gateway was so expensive it priced itself out of our budget."
He also likes that Simpana can deduplicate to tape without having to rehydrate deduplicated data -- a handy feature because Texas Tech hasn't yet completely eliminated tape. Jordan said he added some SAS direct attached storage when he began deduping, but "no Fibre Channel storage or anything expensive."
Texas Tech deduplicates data to a centralized repository in its data center, then sends it off to tape. When the university opens its new DR site by the end of the year, it will move disk to the DR site and replicate with CommVault Continuous Data Replicator (CDR).
Jordan said about 90% of the university's backups are completed within a six-hour window now. He says Texas Tech has been getting a 5.75-to-1 dedupe ratio -- reducing 230 TB of application data to 40 TB of backup up data. He expects that ratio to improve with further tuning.
"We've had a lot of organizational changes in our group that manages backup," he said. "We haven't done a whole lot of tuning with deduplication. It's basically just been thrown out there. We need to look at scheduling and things like that. Some of our applications are 12-, 13-, or 14- to- 1 ratios. I honestly think we can get 8-to-1 or 10-to-1 across the board."
Jordan says about 95% of his backups go to disk, but the rest – including an ERP database and data warehouse -- still go to tape. He expects to eventually get rid of tape, except for archiving at the DR site. "Getting everything else off tape helps, and our tape can support the 5 percent that we back up to it now," he said. "We may continue down that path until maintenance is due on those tape libraries."