The backup rule of three is a simple way to remember backup best practice.
The backup rule of three is a useful concept that helps with business data backup. It came to prominence as a result of photographer Peter Krogh, who used the rule to keep his photography safe. Many people consider the backup rule of three to be best practice despite its roots in photography. The concept reminds businesses how many backup files to keep and where to store them.
The backup rule of three dictates that you should;
- Have at least three copies of your data
- Store the copies on at least two different media types
- Keep at least one of those copies offsite
Three copies of data.
Including your live environment, you should have at least three copies of your data in total. This means that in the event of a disaster you will always have additional versions. We’d recommend creating backup copies at least once every day. However, the more copies you can practically make, the better.
Two media types.
To protect against hardware failure, you should use at least two different media types. A few means of doing this include tape drives, hard drives or the cloud. It is best to ensure that you use both internal storage and a removable (or offsite) alternative. There shouldn’t be an association between the two. Therefore, should one fail, the other will be usable.
One offsite copy.
Keep one copy of your data offsite. Keep that copy separate from the rest of your data. This is to protect against the worst of disasters. For example, flooding may damage your entire business premises, rendering your onsite data storage inaccessible and irreparable.
The backup rule of three and the cloud.
The backup rule of three can be difficult to adhere to, whilst ensuring best practice. For example, removable hard drives offer an alternative media type that you can take offsite. However, it is easy to damage or lose removable hard drives.
Cloud-based backup solutions can assist in these instances. These services provide a reliable, alternative media type to local storage. The cloud utilises offsite data centres, which won’t fail because of an issue within your business. This makes data centres more reliable than other methods of keeping data secure.
If you want to adhere to the backup rule of three, the cloud is an effective means of doing so.