Cloud Disaster Recovery

An IT in­fra­struc­ture failure is a serious problem for companies that requires quick action. That is why it is best to prepare an ap­pro­pri­ate response in advance. One possible solution is cloud disaster recovery. Read on to find out more about the cloud recovery concept, how it differs from other strategies, and what to look out for when making the switch.

Cloud Disaster Recovery or Cloud DR for short refers to an emergency backup strategy for data, ap­plic­a­tions, and hardware that, unlike con­ven­tion­al ap­proaches, relies on storage in the cloud. In the event of a failure, the affected data, ap­plic­a­tions, and other resources can be restored from the cloud at the touch of a button so that business can resume as quickly as possible. Service providers now offer Disaster Recovery as a Service (DRaaS).

The core component of cloud DR emergency backups form digital images of relevant data and con­fig­ur­a­tions to be used as temporary re­place­ments (es­pe­cially for hardware) and as a point of reference for recovery in the event of an emergency. Since these images are stored in the cloud or an external data centre, companies that rely on cloud disaster recovery are on the safe side in the event of local crisis situ­ations such as fires, floods, or earth­quakes.

The third advantage of cloud DR is the high security standard provided by cloud service providers or software houses, which not only en­com­passes digital security of the data – achieved through security and en­cryp­tion software – but storing data in external data centres also provides for better pro­tec­tion against on-site data theft, natural disasters, or fires.

There are three basic ap­proaches to building a cloud disaster recovery solution: Cold Cloud DR, Warm Cloud DR, and Hot Cloud DR. The names in no way represent the tem­per­at­ures main­tained within these system ar­chi­tec­tures, but merely indicate the ease with which they can be im­ple­men­ted.

Cold cloud-based disaster recovery typically involves the simple storage of data or images of virtual machines. These resources are ‘cold’ in the cloud and are unusable without an in­ter­me­di­ate step because the data or images must first be down­loaded and in­teg­rated in the event of recovery.

On the one hand, cold cloud DR is the easiest and most cost-effective approach to implement. On the other hand, these ar­chi­tec­tures tend to have a re­l­at­ively high downtime. These pros and cons should be weighed up from a business per­spect­ive.

Warm cloud DR is a standby approach in which mirrors of all mission-critical data and ap­plic­a­tions are stored with a provider. The du­plic­ated resources are always kept up to date, but no data pro­cessing takes place. In the event of a disaster, the mirrored in­fra­struc­ture can be used for recovery.

A certain amount of downtime is therefore un­avoid­able. Nev­er­the­less, warm cloud disaster recovery makes for fast data recovery. Com­plex­ity and costs are higher compared to the cold approach.

The highest level of com­plex­ity in terms of cloud disaster recovery is the hot approach. Here, the entire workload and all of a company’s data are dis­trib­uted not only across the company's internal IT in­fra­struc­ture, but sim­ul­tan­eously across the resources of the cloud DR provider. Data pro­cessing is live and takes place across both sites. If one site fails due to a disaster, all IT processes can continue without in­ter­rup­tion thanks to the remaining, un­af­fected site.

Hot Cloud DR is the only ar­chi­tec­ture with no downtime, but this comes at a price. The cost of the two complete in­fra­struc­tures running in parallel is sig­ni­fic­antly higher than a cold or warm DR framework.

Whether locally or in the cloud, a disaster recovery plan that is optimally tailored to the needs of the company is not forged overnight. When planning business con­tinu­ity, choosing the right partner is not the only issue. We have sum­mar­ised some useful tips to help you make the trans­ition to a disaster recovery plan in the cloud.

Even if you hand over most of the re­spons­ib­il­ity and man­age­ment effort to a provider with a cloud DR solution, you still need people within the company to oversee the planning and main­tain­ing of data pro­tec­tion. Trained personnel who are aware of their tasks and duties are therefore essential for an efficient cloud disaster recovery strategy.

It must be clearly defined in which cases a cloud DR comes into play. Is the solution already required for when certain ap­plic­a­tions fail or in­di­vidu­al data is lost? Or does ‘disaster’ refer to classic cata­strophes such as earth­quakes, flooding, fires, and the like?

The choice of provider plays an important role in cloud DR. Companies need to consider many factors that extend far beyond typical factors such as costs or con­trac­tu­al terms. On the one hand, the selected provider should meet data pro­tec­tion and security re­quire­ments, like the GDPR. The avail­ab­il­ity of ad­di­tion­al services is another decisive factor. For example, if you prefer to keep efforts to a minimum, a Managed Service Provider that offers the complete DRaaS package is the best solution.

Many companies tend to rent hardware and software resources from a single provider in order to keep track of their rented services. But this makes them heavily dependent on the provider. You should keep this so-called ‘lock-in’ effect in mind when selecting your cloud disaster recovery (and when choosing other new cloud services).

In the best-case scenario, you won’t ever have to draw on your cloud DR plan. But this shouldn’t be assumed. It is a good idea to test your cloud disaster recovery concept in advance in co­oper­a­tion with your provider to avoid any issues or in­sec­ur­it­ies as to whether your plan will work when an incident arises.