# Document history for the Microsoft SQL Server on Amazon EC2 User Guide
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The following table describes the documentation releases for Microsoft SQL Server on Amazon EC2.

| Change | Description | Date | 
| --- |--- |--- |
| [EC2 High Availability for SQL Server](https://docs.amazonaws.cn/sql-server-ec2/latest/userguide/sql-high-availability.html) | Amazon EC2 High Availability for SQL Server allows you to configure instances running license-included SQL Server as part of a HA cluster to reduce licensing costs. | November 17, 2025 | 
| [Database backup and restore with Amazon VSS solution based snapshots](https://docs.amazonaws.cn/sql-server-ec2/latest/userguide/ms-ssdb-ec2-bkup-vss.html) | Added support for Amazon VSS solution based backup and restore feature. | January 17, 2025 | 
| [Downgrade your SQL Server edition](https://docs.amazonaws.cn/sql-server-ec2/latest/userguide/downgrade-sql-server-on-ec2.html) | Added a new section about downgrading your Microsoft SQL Server edition. | August 28, 2023 | 
| [Migration](https://docs.amazonaws.cn/sql-server-ec2/latest/userguide/migrate-sql-server-on-ec2.html) | Added a new section about migrating to Microsoft SQL Server on Amazon EC2. | August 1, 2023 | 
| [Initial release](#doc-history) | Initial release of the Microsoft SQL Server on Amazon EC2 User Guide | August 18, 2022 |