What is the Availability zone on Azure?

Microsoft Azure offers multiple high availability options to meet customer requirements. Such options really help to build an application with higher SLA levels for their customers. Azure’s availability zone can help you achieve your organization’s reliability goals.

Availability Zones are unique physical locations with independent power, network, and cooling. Each Availability Zone is comprised of one or more datacenters. Availability Zones are tolerant to datacenter failures through redundancy and logical isolation of services.

Availability zone – Supported Azure Regions

At the time of writing this article, availability zones are supported only in North America and Europe. (Look at white dot locations in the below image to know the availability regions.). Get the latest information by referring to the Microsoft Azure portal. Availability Zones are physically separate locations within an Azure region. Each Availability Zone is made up of one or more data centers equipped with independent power, cooling, and networking.

Let’s pick any of the regions to drill down to further explore availability options. The availability zone option is not available in all the Azure regions. It’s mostly available in selected US and UK regions.

East US regions offer 3 availability zone. Each zone might consist of one or more data centers.

Azure resilience capabilities:

Refer “zonal redundancies” section on the below image.

Download Azure infrgraphic

• Compute- 4 9s (SLA)
• Storage – 12 9s (SLA)

How your application can be protected using the availability zone?

It’s very simple. Deploy redundant application servers in a different availability zone. The following deployment example from azure portal which shows that deploy IaaS VM in each availability zone and configure zone redundant SQL using DBaaS. The zone redundant load balancer routes the traffics to application servers which are deployed in each region. If we lose one region, still your application will be available from other regions. This is one of the classical example that how you can protect your application by leveraging the availability zone.

Hope this article is informative to you.