Ever since tape and disk were first developed in the 1950s, there has always been a debate raging amongst computer experts between the speed of disk and the stability of tape.
Obviously, disk is incredibly fast because you can access data randomly. That’s why it’s the media of choice for primary access. But because they have so many moving components, hard drives are far too unstable to be used as long-term or archival storage.
And because tape is such a simple and durable media, it’s the perfect long-term backup device. But the drawback of relying on tape is that data can only be accessed in a linear fashion, making it somewhat slow.
Companies wishing to have both – speed and reliability – would have to perform 2 separate backups every day.
- One copy would go to a set of hard drives which were kept on-site. These would be a short-term backup for fast emergency recovery.
- Another copy would be saved to tapes that would be taken to an alternate location. These would be used as a long-term archival backup, and would also serve as a last-resort in the event of a major catastrophe.
As you can imagine, this process involved a lot of manual labour and was vulnerable to human error. Then, along comes “cloud” storage. Storing data over the web is great because the reliability of “cloud” is on par with (or better than) traditional tape media. (Assuming that your cloud backups are copied redundantly across multiple locations)
But the real power of cloud-based storage is that backups can be completely automated, and there are no physical devices to touch.
Now, companies can implement a 100% automated process where short-term daily backups are sent to on-site disk storage for fast restores, and an additional copy is transferred over the Internet to a remote facility for long-term storage and critical disaster recovery. This Disk-To-Disk-To-Cloud approach offers speed and reliability, while greatly reducing the need for human involvement in the data protection process.
And the D2D2C methodology also has 2 other unexpected benefits:
- Off-site cloud backup copies are usually encrypted before transmission. This is a major security improvement since most companies don’t encrypt their backup tapes before taking them off-site.
- Because there are no tapes to fill or switch, companies are no longer bound to a daily backup schedule. Now they can incrementally back up every 2 minutes if they want, without negatively affecting performance. This greatly reduces the potential for data loss.
D2D2C is the future of backup. Companies love it because it’s fast and secure, and IT guys love it because they finally get to leave work at a reasonable hour instead of staying late to switch tapes.