I’ve heard the horror stories, and I’m sure you have too. A company thinks they’re covered because they have replication running, only to realize too late that replication doesn’t protect against data corruption or ransomware. In a disaster scenario, every copy of their critical data is compromised. And then comes the dreaded question: Do we have a backup?
Many teams—even those with seasoned IT professionals—misunderstand the fundamental difference between backup and replication for disaster recovery (DR). Replication is about availability, or keeping systems running with minimal downtime. Backup is about recoverability, or ensuring you can go back to a known good state.
This post breaks down replication, backup, and their respective roles in disaster recovery in a way that’s easy to share with your team, helping to prevent costly misunderstandings.
What is data replication?
Data replication involves copying and synchronizing data between your primary site and the DR destination in real-time or near real-time. It offers fast failover capabilities as the replicated data at the DR site is constantly updated. However, if malware infects your primary site, it might also replicate to the DR site, rendering the backup compromised.
What is data backup?
Data backup involves creating full and incremental copies of your data and storing them in a separate location from your primary system, typically on a scheduled basis, to prevent loss, corruption, or disasters. A couple key points:
- Incremental backups capture changes in data, thus offering a point-in-time recovery option.
- Ideally, backups are immutable, meaning they can’t be altered, in order to protect against malware and ransomware by making files and images read-only for safe recovery.
- Air-gapped and offline backups can further help resist malware and ransomware attacks by creating a virtual or physical separation from the production network.
- Cloud-based backups are a great option for addressing these requirements while offering affordable scaling options as the environment grows.
Replicating backups
A hybrid approach involves replicating your backups to a secondary location, offering a balance between data protection and recovery time. This can be between on-premises and cloud environments, or across multiple cloud targets.
While replicating backups offers additional protection and accessibility for online recovery, the backup images are still subject to ransomware infection. Using immutable backups helps prevent the spread of the infection to recovery sites and backup repositories.
Data backups paired with replication can be an ideal strategy. Full and incremental backups with point-in-time snapshots can provide regular recovery points with replicated copies for remote recovery and additional protection.
Cloud Replication
Backblaze B2 Cloud Replication enables your data to be automatically copied from one location to another for redundancy, compliance, and fast local access. Create 2x backups for a stronger disaster recovery posture. Replicating your Backblaze data is easy and free—no service or egress fees—just the standard Backblaze B2 Cloud Storage rates.
Disaster recovery and backups: Factors to consider when choosing the right approach
The optimal approach to disaster recovery backup and when and how you use replication depends on your specific needs.
- For frequently accessed data requiring near-instantaneous recovery, consider a combination of a hot site methodology and real-time data replication. This offers the fastest failover, but can come at a higher cost.
- For critical data with acceptable downtime, a warm site with replicated immutable backups at a secondary location (either on-premises or in the cloud) provides a good balance between cost and recovery time. While requiring some manual intervention, it offers protection against malware replicating to the DR site.
- For less critical data or archival purposes, cold storage with periodic backups is a cost-effective option. Backups offer a historical record and are less susceptible to malware infection compared to replicated data, particularly if Object Lock is enabled for immutability.
Data replication is important, but it should not be seen as a substitute for backups. Backups offer a required safety net, providing a point-in-time recovery option even if the replicated data is compromised. Selecting the right disaster recovery backup strategy depends on a careful evaluation of your company’s specific needs, budget, and risk tolerance.
By understanding the pros and cons of each option, you can make an informed decision that ensures optimal protection for your critical data in the face of unforeseen disruptions.
