We are very happy to announce Public Preview of the ability of migrating an existing Azure Data Explorer (ADX) Cluster to support multiple availability zones. By using availability zones, a cluster can better withstand the failure of a single datacenter in a region to support business continuity scenarios. The feature will allow clusters that were deployed not supporting zones, to be seamlessly redeployed to support multiple zones.
When availability zones are configured, a cluster's resources are deployed as follows:
- Compute layer: Azure Data Explorer is a distributed computing platform that has two or more nodes. If availability zones are configured, compute nodes are distributed across the defined availability zone for maximum intra-region resiliency.
- Persistent storage layer: Azure Data Clusters use Azure Storage as its durable persistence layer. If availability zones are configured, ZRS is enabled, placing storage replicas across all three availability zones for maximum intra-region resiliency.
To add availability zones to an existing cluster, you must update the cluster zones attribute with a list of the target availability zones using one of the following methods:
- REST API
- C# SDK
- Python SDK
- PowerShell
- ARM Template
Migration to multiple availability zones is supported in all regions that support availability zones but is limited to regions that don't have capacity restrictions. Check in our documentation the list of currently supported regions.
Using availability zones incurs additional Storage costs.
For more information go to the feature's documentation.
