remote admin connections (server configuration option)

Applies to: SQL Server

SQL Server provides a dedicated administrator connection (DAC). You can use the DAC to execute diagnostic functions or Transact-SQL statements, or to troubleshoot problems on the server, even when the server is locked or running in an abnormal state and not responding to a SQL Server Database Engine connection.

By default, the DAC is only available from a client application directly on the server. To enable client applications on remote computers to use the DAC, use the remote admin connections option of sp_configure.

By default, the DAC only listens on the loop-back IP address (127.0.0.1), port 1434. If TCP port 1434 isn't available, a TCP port is dynamically assigned when the Database Engine starts up. When more than one instance of SQL Server is installed on a computer, check the error log for the TCP port number.

The following table lists the possible values for the remote admin connections option.

The following example enables the DAC from a remote computer:

EXEC sp_configure 'remote admin connections', 1;
GO
RECONFIGURE;
GO

• Diagnostic Connection for Database Administrators
• Connect to SQL Server when system administrators are locked out