Cross-Availability Zone ENA Express support for Multi-AZ deployments - Amazon Relational Database Service
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Cross-Availability Zone ENA Express support for Multi-AZ deployments

Amazon RDS supports Cross-Availability Zone ENA Express for eligible DB instance classes in Multi-AZ deployments using AWS's Scalable Reliable Datagram (SRD) protocol. Cross-Availability Zone ENA Express increases single-flow network bandwidth enabling faster block-level data replication between primary and standby DB instances.

For more details on SRD and for a list of instance classes that support Cross-Availability Zone ENA Express, see ENA Express in the Amazon EC2 documentation.

Note

Cross-Availability Zone ENA Express is not supported for Amazon RDS for SQL Server.

Benefits

With Cross-Availability Zone ENA Express enabled, Multi-AZ deployments see an increase in single-flow bandwidth for data replication between Availability Zones. With advanced congestion control and multi-pathing capabilities, Cross-Availability Zone ENA Express reduces replication latency and replication latency variability and improves failover reliability for write-intensive workloads.

Actual throughput depends on the aggregate bandwidth limit of the DB instance class, the database engine, and your database configuration.

Enabling Cross-Availability Zone ENA Express

Cross-Availability Zone ENA Express is enabled by default on all newly created Multi-AZ DB instances that use eligible instance classes.

To enable Cross-Availability Zone ENA Express on an existing Multi-AZ DB instance, do one of the following: