Focusing on Disaster Recovery: AWS's and Azure's DR Solutions Compared
Since going offline for even one hour can cost thousands of dollars, it's important to know which cloud services are most reliable in a crisis.
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Are you adequately prepared for an unexpected IT outage? Disaster recovery is a critical aspect of business continuity that entails processes and procedures aimed at recovering or continuing vital IT systems and infrastructure after a natural or human-induced disaster.
The online statistics portal Statista reports that globally, one hour of critical server downtime costs 24 percent of businesses between $301,000 and $400,000, and in total, 81 percent of businesses report costs in excess of $301,000 per hour of critical server downtime.
Cloud computing has led to a new way of preparing for IT disasters by providing secondary environments for backing up and restoring data, and failing over business applications. These disaster recovery services are cost-effective and straightforward to set up. Microsoft Azure and Amazon Web Services (AWS) are two of the leading providers of disaster recovery solutions at present. This article overviews and compares AWS and Azure’s disaster recovery services.
AWS Disaster Recovery
AWS has a number of different cloud services available, some of which you can use for disaster recovery purposes. There is no dedicated AWS disaster recovery service, per se, but the range of options gives excellent flexibility.
- Amazon S3 is a service for storing data as objects, which means each file is stored in a repository without any file hierarchy. This service provides excellent durability, meaning transactions are guaranteed to save permanently even if the system crashes. S3 is best for mission-critical data, and using it as primary storage means the data is accessible even if on-premise systems go down.
- Amazon Glacier is a low-cost storage service which is ideal for data archiving and backup. This service should house non-mission-critical data.
- Amazon EBS lets you take snapshots of data volumes and store them on S3. The usefulness of this service is that you can quickly attack an EBS snapshot to a running EC2 instance, ensuring the quick return of enterprise app functionality after a disaster. The EC2 instance handles the application workloads while the EBS snapshot provides primary storage for apps.
- EC2 provides compute capacity in the cloud in the form of virtual machines, which you can spin up in minutes. You can spin up an EC2 instance with machine images that have been preconfigured with operating systems and application stacks. This is an important service for restoring mission-critical applications after a disaster.
- Route 53 is a DNS web service that can route website visitors to your website through multiple endpoints in case your web servers go down after a disaster.
- Amazon VPC allows you to provision a private, isolated section of the AWS cloud on which you can launch AWS resources in a virtual network. Amazon VPC extends your network infrastructure to the cloud, making it easy to continue running important enterprise applications after an on-premise outage.
- Amazon RDS is a cloud-based relational database service that lets you run your production databases in the cloud after a disaster. You can also have a replica of your database running in another region.
Azure's Disaster Recovery
Azure’s disaster recovery options can be distilled into two important services: Azure Storage and Azure Site Recovery.
Azure storage is similar to S3 in that it provides cloud-based object storage for your important data. Azure provides its storage service as a managed service so maintenance and other issues are handled for you. You access your data from anywhere online via HTTP or HTTPS.
Third-party services can also integrate with Azure to reduce Azure storage costs. The reduced costs come from implementing non-standard processes to improve storage efficiency, such as data deduplication and compression. Cloud providers usually compress stored data, but any cost savings from this are not typically passed on to end users.
Azure Site Recovery
Azure Site Recovery is a dedicated disaster recovery service that promises to reduce application downtime for outages that occur and affect either on-premise apps or virtual (cloud-based) apps. You can use Site Recovery as a secondary environment for running apps.
You also have the option of reducing reliance on enterprise infrastructure altogether by running your app primarily in the Azure cloud and using Site Recovery for disaster recovery between different Azure regions.
The service promises low recovery time objective (RTO) and recovery point objective (RPO), both of which are important targets in any disaster recovery plan. The RTO is the target time you set for recovering IT infrastructure that supports important business activities, while RPO is your company’s acceptable level of data loss expressed in time. If a given system has a 45-
minute RPO, you need to back up that system every 45 minutes.
Both AWS and Azure provide disaster recovery options with excellent durability, scalability, and pay-as-you-go pricing options.
Where they differ is that AWS doesn’t provide a dedicated disaster recovery service — you can use its services suite to address different aspects of disaster recovery, such as Network, Compute, or Storage. The advantage of AWS in this regard is that it offers more flexibility in choices, however, Azure Site Recovery and Azure Storage arguably provide everything you need for a successful disaster recovery strategy that utilizes the cloud.
Cloud providers have changed the game when it comes to disaster recovery by providing cost-effective secondary environments for data, application workloads, and network infrastructure to combat problems associated with unexpected outages. Given the costs of just one hour of downtime, the smooth and quick recovery of mission-critical IT infrastructure after a disaster can make a huge difference to the survivability of a business.
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