| ionally, many businesses have at some point done | | | | disk locally, replicates the backup to offsite disk, then |
| backup directly to relatively inexpensive tape | | | | backup to tape there. One will never have to touch |
| systems. For many computer applications, it's | | | | the tapes as they're offsite already. In order for this |
| important to have data immediately ready to be | | | | to work though, you have to have something that |
| restored from a secondary disk if and when the data | | | | changes the way backups are done. It simply cannot |
| on the primary disk becomes inaccessible. The time | | | | be completed with traditional backup software |
| to restore data from tape would be considered | | | | because there would not be enough bandwidth to |
| unacceptable. On the other hand, tape is a more | | | | replicate full and incremental backups. |
| economical alternative for long-term storage | | | | When it comes to disk-to-disk tape, there are |
| (archiving). Because it's also more portable, tape is | | | | numerous manufacturers of hardware and software |
| often used for off-site backup and restoration in | | | | that will copy the data across. Most recently |
| case of a disaster. | | | | introduced is the Assureon, which is a combined |
| Disk-to-Disk-to Tape which is also known as D2D2T, | | | | hardware/software platform that provides |
| refers to backing up data on disks first and tape (or | | | | fixed-content archive storage capabilities for the |
| optical disk) second. Backing up onto tape is | | | | enterprise. This platform is disk-based, and offers |
| performed at less frequent intervals than from | | | | both WORM storage capabilities as well as |
| disk-to-disk. | | | | automated retention periods in which files cannot be |
| As backup and recovery becomes more of a chief | | | | changed or erased until their designated retention |
| concern in the data centers, many storage managers | | | | period has elapsed. |
| are looking to new technologies to make the process | | | | There are those skeptics that feel that disk is not |
| easier. In the near future tape is not going away, but | | | | ready for "prime time." Many others may disagree. |
| it will be increasingly joined by disk as a core backup | | | | SATA Disk based arrays have penetrated every |
| technology. | | | | market, there are millions of these drives "spinning" |
| Tape was the only acceptable method of backup for | | | | and drive failures are rather infrequent. With RAID5 |
| some time. As with any other technology there have | | | | or RAID6 and hot spare implemented the odds of |
| been problems, whether it be the media, the drive | | | | data being lost is extremely slim. |
| library or the backup window. However, backup to | | | | |