Azure Availability Zones: one step closer to Cloud Resilience

All Azure regions, including Switzerland, will soon offer Availability Zones, a feature already present in AWS and Google Cloud regions. This architecture improves resilience by replicating instances between different zones within the same region.

Widespread availability on Azure

Microsoft has announced that, by the end of the year, all existing and newly created Azure regions will offer a minimum of three availability zones. These zones are entities that are both logically and physically separate, thereby increasing the resilience of the services they host. This initiative comes at a time when many decision-makers have become aware of the importance of resilience, particularly following the fire at the OVH datacenter.

Availability zones in Switzerland

In Europe, several Azure regions, such as Paris and Frankfurt, already offer these availability zones. As for the Azure Switzerland North region (Zurich), launched in 2019, it will also have availability zones by 2021. Primo Amrein, Cloud Lead at Microsoft Switzerland, said, “We are constantly developing our local cloud infrastructure to support Swiss customers in their digital transformation. That's why we'll be introducing availability zones in the Switzerland North region later this year.” For its part, Google has already set up availability zones in Switzerland, and AWS plans to introduce these zones in 2022 in its Swiss cloud.

Understanding availability zones

Availability zones, a concept popularized by AWS, are logically isolated data centers spread over one or more physical sites. Each zone has its own network, cooling system and power supply, minimizing the risk of simultaneous failures. These zones are interconnected with minimal latency, guaranteeing efficient replication of data and instances.

Microsoft explains that if one zone is compromised, services, capacity and availability are taken over by the other zones in the region, ensuring continuity of operations.

Exploiting availability zones on Azure

Companies using Azure services can take advantage of availability zones in a number of ways:

• Zonal services: Deploy resources in a specific zone and replicate applications and data to another zone to improve resilience.
• Redundant zone services: Use services that automatically replicate instances across multiple zones in the same region.
• Supra-regional services: Rely on services capable of withstanding the failure of an entire region.

Availability zones are thus a key solution for guaranteeing the continuity of cloud services and meeting enterprise resilience requirements.

Source : ICTjournal