How available are Azure's Availability Zones?

February 18 2021

Azure Availability Zones have garnered plenty of attention in recent months as Microsoft emphasizes the capabilities of these unique physical locations that add fault tolerance for high-availability workloads. For Azure customers, Availability Zones offer opportunities to enhance redundancy, but are these datacenters as "available" as they claim to be? MSCloudNews spoke to professionals about how Availability Zones are serving organizations today and what IT groups are looking for next.

The question of availability

Microsoft designed the Availability Zones offering with unique physical locations, each with independent power, networking, cooling, and logical isolation. This model serves to isolate custom Azure VMs from wider cloud failures. Mark Shavlik, Founder and CEO of cloud security posture management company, Senserva told MSCN:

All cloud vendors can have outages or service slowdowns.  For example the recent Azure Active Directory outage that made it impossible to use Microsoft 365, Azure, Dynamics 365, and custom applications services for five hours in September 2020. This was caused by a software update gone bad… Availability Zones are designed for customers with systems that must be on line as much as possible. Azure does this by isolating the custom Azure VMs from Azure wide failures. 

About Eamon McCarthy Earls

As the assistant editor at and, Eamon helps to oversee editorial content on the site and supports site management and strategy. He can be reached at

Before joining, Eamon was editor for at TechTarget, where he covered networking technology, IoT, and cybersecurity. He is also the author of multiple books and previously contributed to publications such as the Boston Globe, Milford Daily News, and DefenceWeb.

More about Eamon McCarthy Earls