“What’s the difference between backup and disaster recovery?” As data protection specialists, this is a question we often get from clients.
The answer can be somewhat confusing, since the term “Disaster Recovery” can have many different definitions, depending on the context.
For example, disaster recovery can refer to an entire industry, where companies and consultants help organizations respond to catastrophic events such as natural disasters or terrorist threats. Often, these measures have nothing to do with technology at all.
But — in the context of backup and data protection — disaster recovery usually has a very specific definition.
What Is Backup?
With backup, your computer files are copied over to another storage device. As your files change, additional copies — or “backup sets” — of these files will be added to external storage.
In the event of a disaster, you can recover files from your most recent backup set… or recover older versions of your files from a previous backup set.
This “point-in-time file recovery” concept is critical to backup. If you’re not maintaining multiple copies of each file as they change over time, then it’s simply not backup.
A slightly different approach is required when it comes to backing up databases, emails, or other applications. But the basic principles remain the same.
What’s Wrong With Backup?
Backups are fine for recovering files or logical data elements, but they can cause problems in the event of more serious data disasters.
For example, if a server is physically destroyed, the recovery process can be very difficult.
First, you need to purchase a new physical box. Then, the IT administrator has to install all of the original applications. Then, the backup data must be loaded onto the new server. And finally, this server must be configured according to the specifications of the original machine.
Recovering using such a process can take weeks. And that’s why “disaster recovery” systems were invented.
What Is Disaster Recovery?
In the context of data protection, disaster recovery is similar to backup. Except, you’re protecting entire systems instead of just individual files.
Disaster recovery applications usually allow protected systems to perform fast “bare metal recovery” to dissimilar hardware or virtual machines in a fraction of the time that would be required for a traditional file backup recovery.
Disaster recovery applications offer many other important benefits and capabilities, but they go beyond the scope of this article.
In the simplest terms, backup and disaster recovery are very similar. The main difference is that backup is for files, and disaster recovery is for systems.
In order to overcome modern data protection challenges, companies now often require 2 tiers of data protection:
- Backup for individual file protection
- Disaster Recovery for full system protection