Home > APEX > Storage > White Papers > Dell APEX Block Storage for Microsoft Azure > Considerations for Availability Zone deployments
Dell APEX Block Storage allows you to configure a deployment across multiple availability zones in a single region. This makes it possible to place SDSs in different AZs. Said differently, this is a single cluster that can span multiple AZs. If one AZ is down, the cluster is still fully operational. Spreading data across multiple AZs in this way creates federated distributed protection. This topology keeps the resiliency at the base storage layer, instead of relying on complicated resiliency architectures that exist higher up in the application stack. This is not something a standard cloud deployment can provide. Dell APEX Block Storage is unique in this space.
Note: There is a data transfer charge between Availability Zones. For pricing details, see Azure Bandwidth Pricing.
While the multiple-AZ configuration contains the same components as a single-AZ deployment, there are a few noticeable differences to the deployment: