Azure Regions: Regions for Virtual Machines in Azure

let's say I have some money saved in Bank L. I have my ATM card and I have the bank app. You know, just have different access to my money and Bank L's priority is to make my money safe. Bank L has branches spread across regions. They all share my information and I can access my money all across their branches.

Now imagine Azure Regions as a vast Bank L. They've deployed sophisticated technologies to pull this off. Technology like AI.

In this article, I would take through the following.

* What are Azure regions?

* Special Azure regions

* Region pairs

* Feature availability

* Storage availability

It is important to understand how and where your virtual machines (VMs) operate in Azure, along with your options to maximize performance, availability, and redundancy. This article provides you with an overview of the availability and redundancy features of Azure.

1) What are Azure regions?

Azure operates in multiple data centers around the world. These data centers are grouped into geographic regions, giving you flexibility in choosing where to build your applications.

You create Azure resources in defined geographic regions like 'West US', 'North Europe', or 'Southeast Asia'. You can review the list of regions and their locations. Within each region, multiple data centers exist to provide for redundancy and availability. This approach gives you flexibility as you design applications to create VMs closest to your users and to meet any legal, compliance, or tax purposes.

2) Special Azure regions

Azure has some special regions that you may wish to use when building out your applications for compliance or legal purposes. These special regions include:

• US Gov Virginia and US Gov Iowa

  • A physical and logical network-isolated instance of Azure for US government agencies and partners, operated by screened US persons. Includes additional compliance certifications such as FedRAMP and DISA. Read more about Azure Government.

• China East and China North

  • These regions are available through a unique partnership between Microsoft and 21Vianet, whereby Microsoft does not directly maintain the data centers. See more about Azure China 21Vianet.

• Germany Central and Germany Northeast

  • These regions are available via a data trustee model whereby customer data remains in Germany under the control of T-Systems, a Deutsche Telekom company, acting as the German data trustee.

3) Region pairs

Each Azure region is paired with another region within the same geography (such as US, Europe, or Asia). This approach allows for the replication of resources, such as VM storage, across geography that should reduce the likelihood of natural disasters, civil unrest, power outages, or physical network outages affecting both regions at once. Additional advantages of region pairs include:

• In the event of a wider Azure outage, one region is prioritized out of every pair to help reduce the time to restore applications.

• Planned Azure updates are rolled out to paired regions one at a time to minimize downtime and the risk of application outage.

• Data continues to reside within the same geography as its pair (except for Brazil South) for tax and law enforcement jurisdiction purposes.

To ensure customers are supported across the world, Azure maintains multiple geographies. These discrete demarcations define a disaster recovery and data residency boundary across one or multiple Azure regions.

Cross-region replication is one of several important pillars in the Azure business continuity and disaster recovery strategy. Cross-region replication builds on the synchronous replication of your applications and data that exists by using availability zones within your primary Azure region for high availability. Cross-region replication asynchronously replicates the same applications and data across other Azure regions for disaster recovery protection.

Some Azure services take advantage of cross-region replication to ensure business continuity and protect against data loss. Azure provides several storage solutions that make use of cross-region replication to ensure data availability. For example, Azure geo-redundant storage (GRS) replicates data to a secondary region automatically. This approach ensures that data is durable even if the primary region isn't recoverable.

Examples of region pairs include:

(*) Certain regions are access restricted to support specific customer scenarios, such as in-country/regional disaster recovery. These regions are available only upon request by creating a new support request.

4) Feature availability

Some services or VM features are only available in certain regions, such as specific VM sizes or storage types. Some global Azure services do not require you to select a particular region, such as

(a) Azure Active Directory (Azure Active Directory (Azure AD) is a cloud-based identity and access management service. Azure AD enables your employees to access external resources, such as Microsoft 365, the Azure portal, and thousands of other SaaS applications. Azure Active Directory also helps them access internal resources like apps on your corporate intranet, and any cloud apps developed for your own organization.),

(b) Traffic Manager, or Azure DNS. Azure Traffic Manager is a DNS-based traffic load balancer. This service allows you to distribute traffic to your public-facing applications across the global Azure regions. Traffic Manager also provides your public endpoints with high availability and quick responsiveness.

To assist you in designing your application environment, you can check the availability of Azure services across each region. You can also programmatically query the supported VM sizes and restrictions in each region.

5) Storage availability

Understanding Azure regions and geographies becomes important when you consider the available storage replication options. Depending on the storage type, you have different replication options.

Azure Managed Disks

• Locally redundant storage (LRS)

  • Replicates your data three times within the region in which you created your storage account.

Storage account-based disks

• Locally redundant storage (LRS)

  • Replicates your data three times within the region in which you created your storage account.

• Zone redundant storage (ZRS)

  • Replicates your data three times across two to three facilities, either within a single region or across two regions.

• Geo-redundant storage (GRS)

  • Replicates your data to a secondary region that is hundreds of miles away from the primary region.

• Read-access geo-redundant storage (RA-GRS)

  • Replicates your data to a secondary region, as with GRS, but also then provides read-only access to the data in the secondary location.

The following table provides a quick overview of the differences between the storage replication types:

You can read more about about Azure storage replication.

That's it, folks.