What is backup and recovery?

Imagine what would happen if the computer or server running your customer database suddenly crashed.

Being unable to access any customer data without warning would be crippling for virtually any business, and in this situation the first question any business owner is going to ask is “can I get my data back, and how long is it going to take?”,

The answer to that question is going to rely on your backup and recovery strategy.

So, what is a backup strategy?

There are two main reasons why your business needs to have an effective strategy for backup and recovery. They are:

  1. To protect against data loss in the event of an emergency
  2. To understand how soon data will be reinstated after an emergency

Many companies run a nightly backups of critical data and documents, taking a copy or snapshot and storing it somewhere from where it can be retrieved. This approach means that the company could potentially lose up to 24 hours of data if a backup needs reinstating, but for many companies this is an acceptable risk.

However, companies who have a higher reliance on recent data may wish to perform a backup every hour to reduce the risk of potential loss of data.

Increasing the frequency of backups will mean that there are more of them being stored, which means more storage is needed, so then a retention policy needs to be considered. Should backups be kept for a week, a month, 3 months etc. There needs to be a balance between the amount of storage being used and the likelihood of needing to recover data from a specific point in time. A common strategy is to reduce the amount of backups retained over time, for example:

  • 1 per hour for 24 hours
  • 1 per day for 1 week
  • 1 per week for 3 months
  • 1 per month for every month after 3 months for 2 years

Assuming that a company has an effective backup strategy in place, and that the backups themselves have been periodically tested to ensure that they are usable, the next step is to create a recovery strategy which defines how the backups are reinstated.

Every time a snapshot is taken, there is the potential for a large amount of data to be transferred across the company network, which may impact other applications. This may be a deciding factor in when backups are taken.

Also, there are different types of backups – full backups (a copy of all data) or incremental backups (only containing the changes made since the last backup). Incremental backups are usually far smaller so will have less of an impact on the network, and require less storage.

The medium the company is backing up to also needs to be considered. Should the backups be stored on another server, or disk array in a data center? Should they be written to tape, or even pushed to the cloud? Many strategies consider multiple mediums, for example storing recent backups on a fast access medium such as a local backup server to enable faster restore capability, but then archiving older backups into a cloud storage solution.

There are many other permutations depending on whether data is being stored on physical, virtual or cloud devices, and there are many software platforms designed for each variant.

Getting this right is key to a business being able to retrieve the data it needs to be able to survive a hardware or software failure scenario.

But the strategy doesn’t end there.

Assuming that a company has an effective backup strategy in place, and that the backups themselves have been periodically tested to ensure that they are usable, the next step is to create a recovery strategy which defines how the backups are reinstated.

The recovery strategy may involve having spare computers to write the backup image onto, and would then define how to switch systems over to use the reinstated backup, or whether specialist software is needed to reinstate the backup image in place.

Most importantly, the recovery strategy will define how long it will take to recover to a point where the business can continue to operate at it’s full capacity.

Devon Digital Services provide expert assessment and practical implementation of backup policies and systems to keep your data safe, and your business running. Get in touch for more information.