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Azure Availability Zones

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

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

Protection from datacenter failure

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

Build high availability into your BCDR strategy

L o ad Balancer S tanda r d (Zone r edundant) W eb App W eb App A v ailability Zone 1 A v ailability Zone 2 A v ailability Zone 3 W eb App 6 1 7 5 4 2 3
  1. Overview
  2. Flow
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 application on VMs for redundancy and high availability

Build with confidence with 99.99% VM uptime*

Know that your applications 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.

Related products and services

Virtual Machines

Provision Windows and Linux virtual machines in seconds

Load Balancer

Deliver high availability and network performance to your applications

Managed Disks

Persistent, secured disk storage for Azure virtual machines