- You enable the AlwaysOn Availability Groups or Logshipping feature in Microsoft SQL Server.
- The disks that store the log files of the primary and secondary replica in an AlwaysOn Availability Group (AG) have different sector sizes. Or in Logshipping environments, the disks that the store the log files for Logshipping primary servers and Logshipping secondary servers have different sector sizes. For example:
- The primary replica log file is located on a disk that has a sector size of 512 bytes. However, the secondary replica log file is located on a disk that has the sector size of 4 kilobytes (KB).
- The primary replica log file is located on an on-premises local system that has a sector size of 512 bytes. However, the secondary replica is located on a Windows Azure Storage disk that has the sector size of 4 kilobytes (KB).
Note This issue occurs when you use both the new drives that have a 4-KB sector size and the old drives that have a 512-byte sector size. For more information about the new drives, see SQL Server - New drives Use 4K sector size and SQL Server–Storage spaces/VHDx and 4K sector size.
- Transaction log file
- Log backups
This is an informational message that can be safely ignored.
For more information about how SQL Server works with larger sector sizes, see the following post on the support blog:
SQL Server–Storage spaces/VHDx and 4K sector size
You can use the Fsutil command prompt utility to determine the Bytes per Physical Sector value. If this parameter isn't visible in the output, you must apply the hotfix that's specified in KB article 982018 .
To verify the kind of drive that you have, follow these steps:
- Run the following command at an elevated command prompt: Fsutil fsinfo ntfsinfo x:Note The x placeholder represents the drive that you are checking.
- Use the values for Bytes Per Sector and Bytes per Physical Sector to determine the kind of drive that you have. To do this, use the following table:
"Bytes Per Sector" value "Bytes per Physical Sector" value Drive type 4096 4096 4K native 512 4096 Advanced Format (also known as 512E) 512 512 512-byte native