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How to: Configure a Windows Firewall for Database Engine Access

Firewall systems help prevent unauthorized access to computer resources. To access an instance of the SQL Server Database Engine through a firewall, you must configure the firewall on the computer running SQL Server to allow access.

For more information about the default Windows firewall settings, and a description of the TCP ports that affect the Database Engine, Analysis Services, Reporting Services, and Integration Services, see Configuring the Windows Firewall to Allow SQL Server Access, and Connecting to SQL Server over the Internet. There are many firewall systems available. For information specific to your system, see the firewall documentation.

Important

Opening ports in your firewall can leave your server exposed to malicious attacks. Make sure that you understand firewall systems before you open ports. For more information, see Security Considerations for a SQL Server Installation.

The principal steps to allow access are:

  1. Configure the Database Engine to use a specific TCP/IP port. The default instance of the Database Engine uses port 1433, but that can be changed. The port used by the Database Engine is listed in the SQL Server error log. Instances of SQL Server Express, SQL Server Compact 3.5 SP2, and named instances of the Database Engine use dynamic ports. To configure these instances to use a specific port, see How to: Configure a Server to Listen on a Specific TCP Port (SQL Server Configuration Manager).

  2. Configure the firewall to allow access to that port for authorized users or computers.

Note

The SQL Server Browser service lets users connect to instances of the Database Engine that are not listening on port 1433, without knowing the port number. To use SQL Server Browser, you must open UDP port 1434. To promote the most secure environment, leave the SQL Server Browser service stopped, and configure clients to connect using the port number.

Note

By default, Microsoft Windows XP Service Pack 2 enables the Windows Firewall, which closes port 1433 to prevent Internet computers from connecting to a default instance of SQL Server on your computer. Connections to the default instance using TCP/IP are not possible unless you reopen port 1433. The basic steps to configure the Windows XP firewall are provided in the following procedures. For more information, see the Windows documentation.

As an alternative to configuring SQL Server to listen on a fixed port and opening the port, you can list the SQL Server executable (Sqlservr.exe) as an exception to the blocked programs. Use this method when you want to continue to use dynamic ports. Only one instance of SQL Server can be accessed in this way.

Windows Vista and Windows Server 2008 and later

The following procedures configure the Windows Firewall by using the Windows Firewall with Advanced Security Microsoft Management Console (MMC) snap-in. This snap-in is available beginning with Windows Vista and Windows Server 2003. The Windows Firewall with Advanced Security only configures the current profile. For more information about the Windows Firewall with Advanced Security, see Configuring the Windows Firewall to Allow SQL Server Access

To open a port in the Windows firewall for TCP access

  1. On the Start menu, click Run, type WF.msc, and then click OK.

  2. In the Windows Firewall with Advanced Security, in the left pane, right-click Inbound Rules, and then click New Rule in the action pane.

  3. In the Rule Type dialog box, select Port, and then click Next.

  4. In the Protocol and Ports dialog box, select TCP. Select Specific local ports, and then type the port number of the instance of the Database Engine, such as 1433 for the default instance. Click Next.

  5. In the Action dialog box, select Allow the connection, and then click Next.

  6. In the Profile dialog box, select any profiles that describe the computer connection environment when you want to connect to the Database Engine, and then click Next.

  7. In the Name dialog box, type a name and description for this rule, and then click Finish.

To open access to SQL Server when using dynamic ports

  1. On the Start menu, click Run, type WF.msc, and then click OK.

  2. In the Windows Firewall with Advanced Security, in the left pane, right-click Inbound Rules, and then click New Rule in the action pane.

  3. In the Rule Type dialog box, select Program, and then click Next.

  4. In the Program dialog box, select This program path. Click Browse, and navigate to the instance of SQL Server that you want to access through the firewall, and then click Open. By default, SQL Server is at C:\Program Files\Microsoft SQL Server\MSSQL10_50.MSSQLSERVER\MSSQL\Binn\Sqlservr.exe. Click Next.

  5. In the Action dialog box, select Allow the connection, and then click Next.

  6. In the Profile dialog box, select any profiles that describe the computer connection environment when you want to connect to the Database Engine, and then click Next.

  7. In the Name dialog box, type a name and description for this rule, and then click Finish.

Windows XP and Windows Server 2003

The following procedures configure the Windows Firewall by using the Windows Firewall item in the Windows XP and Windows Server 2003 Control Panel which only configures the firewall for the current network location profile. The Windows Firewall can also be configured by using the Windows Firewall with Advanced Security Microsoft Management Console (MMC) snap-in and the netsh command line tool. For more information about these tools, see Configuring the Windows Firewall to Allow SQL Server Access.

To open a port in the Windows firewall for TCP access

  1. On the Start menu, click Run, type firewall.cpl and then click OK.

  2. In the Windows Firewall dialog box, click the Exceptions tab, and then click Add Port.

  3. In the Add a Port dialog box, in the Name text box, type SQL Server<instance name>.

  4. In the Port number text box, type the port number of the instance of the Database Engine, such as 1433 for the default instance.

  5. Verify that TCP is selected, and then click OK.

  6. To open the port to expose the SQL Server Browser service, click Add Port, type SQL Server Browser in the Name text box, type 1434 in the Port Number text box, select UDP, and then click OK.

    Note

    To allow named pipes access through the firewall, you must also enable File and Printer Sharing through the firewall.

  7. Close the Windows Firewall and the Properties dialog boxes.

Note

Click Add Program in the Windows Firewall dialog box for additional options, such as granting access to specific programs and restricting access to certain IP addresses or network subnets. For more information, see the Windows documentation.

To access a program through the Windows firewall

  1. In the Windows Firewall dialog box, on the Exceptions tab, click Add Program.

  2. Click Browse, and navigate to the instance of SQL Server that you want to access through the firewall, and then click Open. By default, SQL Server is at C:\Program Files\Microsoft SQL Server\MSSQL10_50.MSSQLSERVER\MSSQL\Binn\Sqlservr.exe.

  3. To close the Windows firewall program, click OK twice.

For a brief tutorial about how to configure a static port, open the firewall, and connect to the Database Engine by using SQL Server Management Studio, see Tutorial: Getting Started with the Database Engine.