Disaster Recovery or Backup – what’s the difference?
By Adam Flynn
A question that is sometimes asked is what’s the difference between Backup and Disaster Recovery, aren’t they just the same? Whilst both are important, backup is just one part of the disaster recovery process.
Organisations, large and small, that rely on IT, know that Backup is not a luxury but a requirement but the process of how your business recovers that data and its ability to use it afterwards, is equally important. Whether it is your business’ internal documents, customer-facing applications, or the ability to process transactional data – it needs to be protected. Losing data can be a disaster on its own, and can cause even more financial consequences if a business is not able to restore it in a reasonable time. How long could your business be without access to key data and systems depending on the nature of your business it could be days, hours or minutes?
Disaster Recovery is the practice of creating a secondary site to which your primary site will fail over. An analogy to help illustrate the issue would be to imagine if the IT was your car that enables your business, and your data were the wheels. If your car has a flat tyre, you can replace a wheel with a spare (i.e., restore your data from the backup). That assumes the rest of your car is fine and can run. Assuming your spare tyre is exactly the same as your primary (and not a mini-spare), you can use them interchangeably.
Using the car analogy there are some questions which show the difference between Backup and Disaster Recovery.
- How fast can you change the tyre? That’s the ‘Recovery Time Objective’ – and with Cloud-based Disaster Recovery as a Service, you measure that time in minutes however if your business only has backup it may take hours or days to get properly running again.
- What’s the quality of the spare? Some spares are only good for 50 miles of driving. Some are basically the same as your regular tyres. Given the broad range of disasters that could occur, you might want your spare to work for more than a short while – so, get production-level resources. Worst case, you’ll need them for only a short time.
- From what point you can continue driving? That’s the Recovery Point Objective. If your last replication happened 20 minutes ago, you’re 20 minutes behind on the secondary site. If it was an hour ago, that’s 60 minutes behind. Nowadays, with DRaaS, you can really push this down to just a few minutes.
Backup is for data. Of course, having all your data somewhere safe is hugely important for any number of reasons, from a failure to archiving to legal and regulatory requirements. When we talk about disaster recovery, however, we usually mean more than simply backing up the data, or even taking a snapshot of the system image.
The basic litmus test for Backup vs. DR goes like this: if you lose some or all of your data, but your computing environment is fine, backup function will allow you to bring your data back and load it onto your systems, and get your IT service back on track. But if your IT environment itself is not available (your building has burnt to the ground) you don’t have IT systems to bring the recovered data back to. This means that having your data protected is not good enough in cases when you have lost your environment, whether it is power, hardware, software, or network. Sot the difference between backup and disaster recovery is simple:
Backup takes care of your data by periodically saving it in a secure location (on-site or off-site), and bringing it back to you when you need it.
Disaster recovery is a function that replicates your entire computing environment – data, systems, networks, and applications – and makes it available when your primary environment is unavailable.
Ultimately, the Disaster Recovery function provides you with a complementary, redundant environment “on-demand” where you not only can load your data, but can rebuild and run your entire IT service until your primary system is back. Following our earlier analogy with a car, think of it as a rental car or a rental when your own vehicle is being repaired or even you don’t know where it is.