BakBone Blog

Steve Adler, Technical Support & Operations Lead

We back up our data so that in case of a data loss event, we have the ability to restore that data. But how do you protect the data that you’ve backed up. You can send it offsite, but what happens if that offsite location is affected by a catastrophic event? It’s simple really. Make another copy!

NetVault: Backup provides two different ways to make additional copies of your backups. Duplication and Data Copy. What’s the difference?

The Duplication method creates an exact secondary copy which is linked to the original primary backup. During duplication, the copy is broken into segments and stored on the secondary backup device. During restore, segments from the primary copy and the secondary copy are interchangeable. This means that even if you no longer have all of the original tapes, as long as the media that contains the duplicates of that data is available, you’ll be able to restore that data. You can basically “fill in the blanks” with the duplicated data.

However, encrypting that data for added security can pose a problem. It is impossible to unencrypt the primary backup and encrypt the secondary copy because it is not possible to mix unencrypted segments with encrypted segments during restore. If the original saveset is encrypted, the Duplicate method will create an encrypted secondary copy. If you have no encryption for the primary backup, the secondary copy will also be unencrypted.

The Data Copy method is recommended when you want to create a secondary copy for offsite storage. Data Copying a backup breaks the backup into segments and copies the segments onto the targeted backup device. During restore, NetVault: Backup only restores the primary copy or the secondary copy. Backup segments from the primary and the secondary are not interchangeable. This means that if you are missing part of the original backup, you will need the entire secondary copy available to perform a restore. You can’t just “fill in the blanks.” However, this enables the ability to encrypt the Data Copy, or secondary copy, while the primary copy remains unencrypted such as with deduplicated primary backups.

By incorporating one or both of these strategies to copy your data, you can decrease the chance of losing your backups to a catastrophic event so you can recover your data when you need it.