Home > Storage > PowerFlex > White Papers > Dell APEX Block Storage for Public Cloud: Microsoft SQL Server Multi-Subnet Failover Clustering Deployment > Microsoft SQL Server 2022 multisubnet failover cluster on Dell APEX Block Storage for Public Cloud
A multisubnet failover cluster is a highly available solution that enables SQL Server 2022 instances to failover over various subnets. This functionality provides improved availability and disaster recovery capabilities for SQL Server deployments and is especially relevant when the APEX Block Storage cluster is configured across multiple-AZs, each one with its own subnet.
In a multisubnet failover cluster, the SQL Server instances with APEX Block Storage multi-AZ configuration, can be set to automatically fail over in the event if one of the AZs has an outage.
A simpler configuration can be deployed for APEX Block Storage, such as using a single AZ instead of multiple, and for SQL Server, such as using non-clustered configuration. The APEX Block Storage architecture for SQL Server 2022 multisubnet cluster on AWS cloud is used in this paper as a reference architecture for a more highly available solution.
An APEX Block Storage deployment in AWS is set as a two-layer design, in which compute and storage instances are distinct. The two-layer design enables Amazon EC2 instances that are compute oriented for databases and application workloads to be configured and scaled separately from Amazon EC2 instances that are optimized for storage, providing customers with more flexibility.