We are continuing the Azure fundamentals blog series. We are now going to start investigating the Core Azure Services available and how these building blocks can be used to create services within Azure.  

Following the AZ 900 skills measured document, we will start with Regions.  

What is a Region 

As discussed in the Cloud concept overview, cloud computing is a model for providing on-demand computing resources, whether it’s specific applications, storage, or pure computing power. For Microsoft, all these services are hosted within Azure datacenters globally. These datacenters are large buildings containing redundant networking, power, and hardware needed to provide these services all managed by Microsoft on behalf of its users and customers. The location of the regions allows you the services and flexibility to deploy your applications closer to your users in a scalable and redundant manner. However, not all datacenters offer all services or virtual machine features, so depending on your virtual machine size or storage requirements, you could be restricted to a subset of Azure regions.  

These datacenters are not directly exposed to end-users, Microsoft groups them into regions. An  Azure Region is one or more of these datacenters that are physically located close to each other to ensure low-latency networking. Smaller regions will only have a single datacenter, but they still have a number of redundancy features that will be covered in a future post.  

Where are the currently deployed regions 

The various regions are grouped into geographies which are defined by country or geopolitical boundaries to preserve data compliance and sovereignty, i.e., all European datacenters are located and paired to comply with the European legislation GDPR (General Data Protection Regulation). The only exception for this is Brazil South which replicates to US South Central. 

Microsoft also operates more isolated regions for specific workloads that require additional governance, for example, governmental workloads.  

What is Region pairing 

One of the redundancy features Azure offers is Region Pairing. Each Azure region is paired with another neighboring region within the same geography. This pairing is to mitigate full region outages from large scale interruptions.  

The paired region is located at least 300 miles away to be isolated from localized disasters but close enough to be directly connected to ensure low latency for data replication. Maintenance updates are also staggered between pairs to minimize downtime and risk of service outages.  

In extensive outages, Microsoft will prioritize one region in each pair to recover as quickly as possible to restore services within the region pair.  

Summary 

So to summarize, Microsoft supplies datacenters logically grouped into regions based around their physical locations and data compliance requirements. These Azure Regions provide the services and features of Microsoft Azure to allow you to deploy them close to your user base. Azure Regions are paired for addition redundancy to protect from region outages and localized disasters.  

We will continue to review the additional redundancy features and other core features offered by Microsoft in further blog posts.  

—Matt Boyd