Azure Availability Zones

High availability for your most demanding mission-critical apps and data

  • Protection from loss of data centres
  • High-availability option for your comprehensive business continuity and disaster recovery (BCDR) strategy
  • 99.99% SLA on virtual machines

Protection from data centre failure

Availability Zones are unique physical locations with independent power, network and cooling. Each Availability Zone is comprised of one or more data centres and houses infrastructure to support highly available, mission-critical apps. Availability Zones are tolerant to data centre failures through redundancy and logical isolation of services.

Build high availability into your BCDR strategyVirtual machines (VMs) are physically separatedacross zones, and a virtual network is createdusing load balancers at each site. These locationsare close enough for high-availability replication,so your apps stay running, despite anyissues at the physical locations.1234567
  1. Overview
  2. Flow

Build high availability into your BCDR strategy


Virtual machines (VMs) are physically separated across zones, and a virtual network is created using load balancers at each site. These locations are close enough for high availability replication, so your applications stay running, despite any issues at the physical locations.


  1. 1 Create zone-redundant Load Balancer
  2. 2 Create front-end subnet
  3. 3 Create DB subnet
  4. 4 Create VMs in three Availability Zones
  5. 5 Configure zone-redundant SQL DB
  6. 6 Add VMs to the load balancer’s back-end pool
  7. 7 Deploy your app on VMs for redundancy and high availability

Build with confidence with 99.99% VM uptime*

Know that your apps will be running when you need them.

Try with hands-on labs

*99.99% SLA applies to two or more VMs running in two or more zones in the same region.

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