Improving backup and restore capabilities
By Jim Wheeler
Data backups are made for one purpose: to have a duplicate set of data that can be used to reload information onto a failed system and restore that system to use. Tape has been the most relied upon media for backing up data because it was simple and cost-effective to use. However, the explosion of data has put a serious strain on tape systems in terms of capacity, speed and fault-tolerance.
The most common cause of tape-system downtime is the failure of a piece of media or a drive, either of which can result in the failure of the backup or restore operation. If a critical piece of media breaks during a restore operation - well, you can only hope that the data can be recovered somehow. With really critical data, the way to ensure a higher level of protection is to go to the same technology found in magnetic disks: a redundant array of individual devices (RAID).
Just as RAID technology is able to provide increased capacity, increased throughput and redundancy for magnetic disks, so can RAID technology provide these same benefits to tape systems for backup and restore operations.
Multiple drives in a tape library cannot be combined in aggregate to increase throughput in large backup operations, but RAID tape drives can be. Utilizing RAID level three technology allows all the tape drives to be combined to achieve data transfer rates much higher than those
The most common cause of loss in a backup or restore operation, according to data recovery experts, is the failure of an individual tape cartridge or drive. Although multiple tape drives offer protection against the failure of a single drive, there is no protection against the failure of a single piece of media. RAID tape technology allows for continued operations if a tape drive or the tape media fails, and therefore critical data is not lost.
Duplicate data sets - painlessly - and "no trucks" off-site disaster recovery
RAID 1 configuration mirrors data to all five drives, or to one or two mirrored pairs of drives. Using this configuration, two duplicate sets of tapes can be created at the same time. One tape set can be stored off-site for disaster recovery purposes. External mirroring to another tape RAID device can allow for the creation of duplicate tape sets that are already in an off-site, secure location. Recovery operations can proceed without having to waste time physically transporting the tapes directly to the site, or risk loss or damage to the tapes.
Two significant benefits are provided by tape RAID technology: backup performance is improved by up to 400 percent, and it ensures virtually 100 percent backup reliability. Tape RAID technology protects the bottom line while saving business dollars.
About the author: Jim Wheeler is Director of Marketing at Maxoptix Corporation.
This was first published in August 2001