One or more datacentres in an Azure region that are physically apart from the rest and have their own power, cooling and network. If one zone fails, the others keep running.
Read more: Microsoft Learn
In the Ultra Transcenders books
Each book explains Availability zone in context, with comparison tables and the common traps.
Terms in this definition
Related terms
- Dedicated host groups
Collections of physical dedicated hosts that live in one availability zone each, so covering several zones requires a separate group per zone.
- Nonzonal
Describes a resource with no availability zone configuration. Azure can put it in any zone, so it may go offline if that zone fails.
- Zonal
Placed in a single availability zone, as with a Standard NAT gateway. It continues to serve subnet resources located in other zones, but goes down if its own zone fails.
- Zone-redundant
Distributed over every availability zone in a region, allowing it to withstand losing one zone; a StandardV2 NAT gateway is an example.
- Zone-resilient
Keeps working when an availability zone goes down, either by being zone-redundant or through zonal copies spread over several zones with failover between them.
- ZRS
Zone-redundant storage: data is written three times, each copy in a different availability zone of the same region, and nothing is replicated to a secondary region.