Amazon EC2 High Availability for SQL Server on Amazon EC2
Amazon EC2 High Availability for SQL Server (SQL HA) allows you to configure Amazon EC2 instances running license-included SQL Server as part of a HA cluster to reduce licensing costs. This feature identifies the SQL Server standby (also known as passive) instances in your SQL HA deployments and waives SQL Server licensing fees for them, allowing you to pay only Windows rates for these standby instances while maintaining your HA configuration.
Supported SQL Server High Availability deployments
SQL HA supports two SQL Server High Availability deployments, including:
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Always On Availability Groups
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Always On Failover Cluster Instances
For Always On Availability Groups, SQL HA identifies primary and secondary (also knows as standby or passive) replicas and waives the SQL Server licenses on the secondary replicas (Amazon EC2 instances) that are not actively serving read traffic. For Failover Cluster Instances, SQL HA recognizes which instances are active and which are standing by for failover scenarios and waives the SQL Server licenses on the standby instances. For more information about the SQL HA configurations, see Deploy SQL Server on Amazon EC2
Considerations and requirements
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SQL HA supports two Amazon EC2 instances (also known as nodes) per SQL Server HA cluster.
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The SQL HA active instance should have equal or more vCPUs than the standby instance.
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SQL HA saves license costs for SQL Server license-included only. For more information, see SQL Server licensing options.
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SQL HA only supports multi-AZ deployments within the same region. Cross-region deployments are not supported.
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The SQL Server standby node must meet requirements to receive the license savings, including: 1. Does not serve incoming traffic; 2. Does not run active SQL Server workloads; 3. Is not a readable secondary (except master, msdb, tempdb, or model databases); 4. For Always On Availability Groups, there is no standalone database running outside of the Availability Group.
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SQL HA supports SQL Server (Standard and Enterprise Editions) 2017 and later on Windows Server 2019 and later.
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Windows PowerShell must be 5.1 or above.
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Amazon EC2 Reserved Instances are not supported by SQL HA. If you are using Reserved Instances, discounts may not be applied to these instances in the same payer account. We recommend using Savings Plans instead to benefit from both SQL HA license savings and Savings Plans compute cost savings. For more information, see the Savings Plans User Guide.
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This feature may be terminated at any time, in which case AWS will provide you with as much prior notice as is reasonably practicable under the circumstances.
Prerequisites
To get the license savings for your SQL HA workload, your environment must meet several requirements:
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You have SQL Server license-included HA workloads on Amazon EC2. You can use AWS Launch Wizard to simplify the SQL Server deployment on Amazon EC2. For more information, see AWS Launch Wizard for SQL Server.
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AWS Systems Manager Agent (SSM Agent) must be installed and running on the instances in the SQL HA deployment. For more information, see Working with SSM Agent.
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You must attach the AWSEC2SqlHaInstancePolicy managed policy to your instance role or use a custom role with the required permissions for the Amazon EC2 to access your instances, including permissions for AWS Systems Manager to run commands, access to AWS Secrets Manager for retrieving SQL Server credentials, and Amazon EC2 permissions to read instance metadata.
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By default, AWS Systems Manager uses the built-in
[NT AUTHORITY\SYSTEM]user to access SQL Server HA metadata. You will need to store secrets in AWS Secrets Manager only when your security policies have restricted or disabled the[NT AUTHORITY\SYSTEM]account. -
Network connectivity allows AWS Systems Manager commands to reach your instances.
