DISASTER Recovery

Backup, disaster recovery, DRaaS. The IT industry loves lingo and marketeers love branding. The combination can lead to a clutter of terminology that obscures meaning, rather than adding clarity. So, what are the differences, in plain English, between backups, DR, and DRaaS.

•  A backup is simply a snapshot of your data or virtual or physical machine, typically taken once or several times a day. Backups are often automatically configured to happen daily, after close of business
• Stored for a period of time, with a retention policy like “one a day for a month and one a month for a year”
• Kept in a place separate from the primary system, like your home, another data centre, the back of your Land Rover, or, in the case of Backup-as-a-Service, in the cloud.

Backups are good for legal reasons, data protection and so on. Backups aren’t great for business continuity. Why? 

• The last copy you have is last-night or yesterday, which is usually historic . Most business applications change a lot during a day.
• To re-awaken a system from a backup takes time. First, you need a ready-and-working system, rebooted and then you have to mount the backup. The whole process isn’t quick. If the backup is stored off-site, there’s the travel-time of getting it to the primary location, as well.

• DR systems replicate your data on an ongoing basis from a primary location to a secondary location. 
• Usually replication periods are measured in minutes, or even seconds. So, the last copy is fairly up to date.
• The secondary copy is held until it is re-animated via a fail-over trigger
• DR works for business continuity because you can trigger a fail over and be live at the secondary location in minutes. 

DR solutions are effective for business continuity but they can prove expensive. Why?

• Typically, your DR solution lies idle without returning value on investment. Ongoing fully burdened costs can include your data centre (or other alternative site), labour, connectivity, power, infrastructure, and software maintenance. These elements result in large upfront and ongoing operating costs associated with owning your solution.
• Compounding these costs is the need to ensure your DR solution upgrades in lockstep with your production environment. This requirement effectively doubles the costs of each upgrade. 

• If you don’t have access to a secondary location, or don’t want to pay for it, DRaaS enables you to execute the same Disaster Recovery replication with the cloud as your secondary location. 
• The speeds involved are similarly fast: minutes or seconds to recovering systems
• You pay only for storage while the systems are replicating/in stasis,and, once they fail over, you’ll pay for CPU and Memory resources, as you consume them
• The DRaaS subscription effectively moves the burden of maintaining the alternative site to the vendor, eliminating upfront costs and reducing overall operating expenditures.

The reality is that owning and managing your own DR site can cost approximately three times as much as using DRaaS. 

 

DRaaS is a great way to achieve business continuity goals quickly and more cheaply than owning or paying for a secondary location yourself.