Disaster Recovery as a Service (DRaaS)

Disaster Recovery as a Service

With Disaster Recovery as a Service (DRaaS), you can combat incidents that arise such as IT disasters, Natural disasters such as hurricanes and earthquakes, or man-made disasters such as fires or accidents. The tolerance for downtime has decreased as businesses have become more & more reliant on high availability The ability to recover quickly is paramount.

The effects of a disaster can be devastating to a business. Many companies fail subsequent to experiencing a significant data loss. Disaster recovery is a proactive step can take to avoid such damages and potentially affect earnings. Client relationships could be seriously affected should such disasters result in delivery delays or SLAs.

Disaster Recovery as a Service: RPO & RTO

Recovery point objective (RPO) and recovery time objective (RTO) are two significant measurements in disaster recovery and downtime. RPO and RTO help administrators choose optimal disaster recovery strategies, technologies and procedures.

Recovery point objective (RPO):

The recovery point objective is the upper limit quantity of data loss a company can tolerate without having repercussions to the recovery of operations.  RPO is the maximum age of files that an organization must recover from backup storage for normal operations to resume after a disaster. If an organization has an RPO of two hours, the backup must be taken by the system at least every two hours to meet that objective.

Recovery time objective (RTO):

The recovery time objective for an organization can be defined as the time required to recover files from off-site and local backup storage and resume normal business activity from the time of a failure.  The RTO is the maximum amount of downtime an organization can handle without being functional. A 2 hour RTO on file recovery should not exceed a 2-hour window. This would be outside of the objective window and cause risk to the company.

Meeting tighter RTO windows requires positioning secondary data that admins can access it faster. Recovery-in-place is one method of restoring data more quickly. This technology moves back up data to a live state on the backup appliance, eliminating the need to move data across a network. It can protect against storage systems and server failures.

Preparing for a disaster requires a scrutinized methodology that encompasses hardware and software, networking equipment, power, connectivity, and testing that ensures DR is achievable within RTO and RPO targets. Implementing a thorough DR plan can be tricky but proper planning and implementation will yield significant benefits.

Replication Types for Disaster Recovery as a Service:

Synchronous Replication:

In synchronous replication, the secondary storage device at the receiving end acknowledges the changes being received from the primary device. After receiving the acknowledgment, the primary device/sender sends an acknowledgment to the server that the data has been written. Data is safely stored on both devices before the server/application sends additional data.  “Hot” backup site is required to implement this method and it is most effective in combination with “hot” fail-over and Global Server Load Balancing (GSLB) solutions. Synchronous replication is considered ideal when both source and target are in the same data center.

Semi-Synchronous Replication:

This method of synchronization is parallel to the “warm” fail-over approach. In this method the receiving system acknowledges after a series of changes have been received. Implementation of this method can lead to some data loss as well as a reasonable amount of downtime

Asynchronous Replication:

Asynchronous data replication is faster but less secure. The sending system simply continues to send data, without receiving any response. Parallel to the “cold” fail-over approach, this method is best suited for static resources or scenarios in which data loss is acceptable.

What changes in cloud?

The benefits of a Cloud-based DRaaS solution are:

  • Lower costs, with the Pay-as-you-go
  • Simpler entry point to implementation than traditional methods
  • Less recovery time during fail-overs
  • Ability to switch to powerful servers form low cost only as needed

Hardware independence of virtual servers, varying operating systems, applications, patches and data can be safely and accurately transferred from one data center to a another easily. Back-end maintenance is taken care of by the service provider and is accessible by the enterprise at any given time.

Benefits of Disaster Recovery as a Service:

Many companies are turning towards the cloud for their production environments. As disaster recovery can be complex and time-consuming, it pays to plan ahead to figure out what your business needs. Backup of your entire system including operating systems, security configurations, and software applications makes a complete disaster recovery plan to your business data. 

Cloud-based recovery systems create an image of your entire server to a backup device of your choice housed inside your office.   A copy of your server’s image is uploaded regularly to the cloud.

Faster recovery

Cloud-based disaster recovery and traditional recovery practices are different in terms of RPO and RTO. Cloud-based DR makes your site capable to recover from a warm site right away. Ultimately, reducing your RPO and RTO times significantly from days, or even weeks, to hours. Traditional disaster recovery involves booting up from a cold site for longer recovery times. The cloud recovery experience is greatly reduced.

Thanks to virtualization, the entire server, including the operating system, applications, patches, and data are encapsulated into a single software bundle or virtual server. This virtual server can be copied or backed up to an offsite data center and spun up on a virtual host in a matter of minutes in the event of a disaster. For organizations that can’t afford to wait after a disaster, a cloud-based solution could mean the difference between staying in business or closing its doors.

Cost savings

Cost savings in one of the major advantages of disaster recovery planning in the long term. As you can pay for storing only what you need. Without capital expenses to worry about, you can use “pay-as-you-go” model systems that help keep your expenditures low. With an effective Disaster Recovery Service strategy in place, companies can recover faster, avoiding the costs of lost revenue and lost customers associated with downtime. With a number of partners, vendors and customers that your business interacts with, a DR plan can help save those relationships amidst disaster. 


DR in the cloud allows flexibility, so increasing or decreasing your storage capacity as your business demands it is easier than traditional backup. The cloud option can be easily scaled up or down depending on business requirements. Payment for service will only be for actual use and data center redundancy is handled by the cloud provider. Subsequently, cloud DR is a much cheaper option compared to traditional backup implementations.

Easy back-ups and restore from the cloud

Data backup in real-time or scheduled intervals is possible because of the convergence of cloud computing and business continuity. This procedure can be automated, and servers can be configured appropriately. In case of a disaster, recovery and restoration are implemented quickly and easily. Cloud-based DR is more reliable than conventional backups as potential corruption is increased using single tapes, disks, or flash drives.

Less Dependency on Infrastructure

Dependencies are reduced on physical infrastructure using cloud-based DR.  virtual machines have high compatibility for migration between hardware servers which is one of the greatest benefits. Hardware used in the cloud is abstracted for customers; VMs can be migrated and run in the cloud just as they can run on physical servers.

There are different variances to replicate and be Disaster Ready, in my next blogs I will walk you through with below options.

  1. Protect Azure to Azure using ASR and be ready for Disaster
  2. Protect On-premises Hyper-V Environment to Azure
  3. Protect On-premises VMWare / Physical Boxes to Azure

About the Author Vikrant