The Difference between Backup and Disaster Recovery
While they definitely work together to provide data protection, backup and disaster recovery (DR) are not the same thing. A number of people, especially in smaller and medium-sized businesses, mistakenly think that just doing backups is enough to cover their DR requirements. They think that just doing backups is all the protection that they need from disasters.
The importance of backups cannot be overstated and they do constitute the foundation for an effective DR strategy. However, while there certainly is overlap and in many cases backups can be used as a part of a DR process, backups do not eliminate the need for a DR plan. A backup is essentially a copy of the data that you can use to restore your systems to the point-in-time that the backup was taken. In contrast, a DR plan enables you to recover your essential business processes in the event of a large scale outage caused by a disaster, malware, human error or some other type of occurrence. Let’s take a closer look at the differences between backups and DR.
Backups are a point-in-time copy
Backups are a point-in-time copy of your data. There are several types of backups. Full system backups can be used to restore an entire computer system but more often backups are used to restore a single deleted or corrupted file. In addition to being used for restores, backups also fulfill the need for long-term data archival which can be required for legal or regulatory compliance issues. While backups are vital, the ability to restore those backups is even more important. To ensure that they can reliability restore their backups many businesses follow the 3-2-1 rule of backup where you should have at least three copies of your data, two of which should be kept on different media, and one copy should be stored offsite.
Disaster Recovery is about restoring services
DR consists of more than a backup. A DR plan is a set of planned operations that are designed to restore critical business processes in the shortest possible time with a minimal amount of data loss. DR plans include backups but depending on the needs of the business they can incorporate other technologies like replication was well. Many times a DR plan consists of the steps required to failover your primary environment to a secondary DR location that is either in a separate geographical site or in the cloud. Making a DR plan consists of analyzing your applications, ranking them in terms of recovery priority and identifying their requirements and dependencies. Next, you need to determine your Recovery Time Objectives (RTOs) and Recovery Point Objectives (RPOs). RTOs represent the acceptable time that can elapse before recover your services. RPOs represent that amount of data that your organization can afford to lose in the event of an emergency.
DR builds on backup
Backups are an essential part of an overall DR plan and you should integrate both backup and DR planning into your data protection strategy. Backups have longer RTOs and RPOs and you should think of them as your last line of defense. DR technologies like replication can provide much shorter RTOs and RPOs but they require additional investments in technologies and resources. Backups are not a substitute for DR plans. The combination of backup and DR ensures that your IT infrastructure can survive outages and disasters and be back online in the shortest possible time with as little data loss as your business can tolerate.