Disk replaces tape
While many IT shops say that shipping tapes off-site remains part of their disaster recovery plan, they have taken the recovery portion of the phrase to heart. Because recovering data from tape is time-consuming and costly and because of a rash of highly publicized tape losses, IT has increasingly adopted backup technologies that let them save data to disk instead of tape. With disk-based systems, recovery is much faster than that of tape, and also more reliable. Users no longer have to check and recheck for media errors, and tapes do not have to be shipped off-site to an Iron Mountain or Sungard facility, where it may take as much as two days to get them back in the event of a failure.
As disk-based backup is replacing tape as a backup media, tape is being moved down in the storage food chain. It is being used as an insurance plan should all other measures fail.
Technologies such as virtual tape library (VTL) software and hardware also are taking the place of tape. In a VTL installation, the software backs up data to Serial Advanced Technology Attachment or secondary disk just as it would to tape, unaware that the emulation is taking place. IT recovers data in the same manner as it would recover data from tape, but because it is installed on disk, they can recover it faster.
Jeff Mery, data center and enterprise storage manager for National Instruments, implemented a disk-based backup system from Overland Storage last year.
"Our multivendor backup environment became increasingly more difficult to manage," Mery says. "At times, people had to come in over the holidays to replace tapes or add new ones to the system."
Taxed with backing up the crux of National Instruments' business -- the Oracle's E-Business Suite -- Mery became concerned that the company was outgrowing its tape library system. He moved his storage operations to a disk-based backup system, which backs up his servers and expensive primary storage. The system consists of Overland's REO 4000 disk-based appliance.
By moving to disk, Mery has cut backup times in half and saved time jockeying tapes in and out. After data is backed up to disk, it is moved to an Overland NEO 8000 tape library at Mery's leisure.
Protecting data continuously
In CDP implementations, data changes are continually saved to disk, and recovery can take place based on an extremely detailed time sequence. Users can simply roll back the recovery of data to seconds, minutes or hours before the event occurred, and because it is a disk-based technology, recovery is fast.
Steve Wilson is a one-man IT shop at Cincinnati Thermal Spray. He's put a new face on data protection to protect his headquarters as well as three remote offices, in the U.S.
"Symantec's CPS [Continuous Protection Server] really closes the loop for me," Wilson says. "I am getting as close to a real-time backup as can be achieved across my wide-area link and all data resides on a single server that I can then back up weekly to tape."
Wilson uses Symantec's CPS software at each of four offices to back up 1TB of data. CPS, which installs on a Windows server, backs up data as a series of snapshots to a CPS system and storage located in Cincinnati Thermal Spray's Cincinnati data center.
Because there are tornadoes in the Midwest, Wilson is working to setup alternative work sites in a number of locations for users in an emergency.
"We snap data at the end of every shift," Wilson says. "After some experimentation, we found that that was the best fit. We can capture any changes that might have occurred on the shop floor. Engineers can actually go into the Web interface to recover data they may have inadvertently lost."
While Wilson would not disclose what he paid for the CPS system, he says the savings in manpower alone are enormous. "What used to take an hour or two to restore a single file, now takes about five minutes," he says.
This same technology has proven to be beneficial for larger businesses such as Baptist Memorial Healthcare in Memphis. Here, Hal Weiss, systems engineer, has put in Revivio's CPS 1200 to protect his business-critical financial data.
Other companies making CDP products include TimeSpring, Mimosa Software, Microsoft, IBM, HP, EMC and XOSoft. Some CPS software such as Symantec's and Microsoft's use snapshots to back up data as often as 64 times a day. Other systems such as Mimosa Software, EMC, HP and TimeSpring back up data continuously and with time-sliding software can reverse a backup to any known good state within minutes of the failure.