Microsoft KB Archive/810322

= BUG: Commerce Server Cannot Connect to a Clustered Named Instance Through a Firewall =

Article ID: 810322

Article Last Modified on 4/29/2003

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APPLIES TO


 * Microsoft Commerce Server 2002 Standard Edition
 * Microsoft SQL Server 2000 Enterprise Edition

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SYMPTOMS
After you install Commerce Server, you may not be able to view Commerce Server parameters in the Microsoft Management Console (MMC). When you right-click Commerce Server Manager, click Properties, click Modify, and then click Test Connection, you may receive the following error message:

Test connection failed because of an error in initializing provider. [DBNETLIB][ConnectionOpen (connect).]Specified SQL Server not found.

This error occurs when you try to connect to a clustered named instance of SQL Server through a firewall



CAUSE
When Commerce Server connects to a computer that is running a virtual instance of SQL Server, and if Network Address does not specify the destination TCP port, the client library queries the server on port UDP 1434 to collect information about the instance.

When the server returns the information, the network frame contains the IP address of the physical node instead of the IP address of the virtual server. Depending on the firewall configuration, this network packet may be dropped, and the client may not receive any answer.



RESOLUTION
You must specify the listening port of the named instance in the Commerce Server connection string. By default, the SQL named instance listens on port 1434.

To resolve this problem, follow these steps:  Find the listening port number of the SQL named instance.  Open SQL Enterprise Manager. Right-click the appropriate instance in the SQL Server Group. Click Properties. In the SQL Server Properties dialog box, click the General tab, and then click Network Configuration. This opens the SQL Server Network Utility dialog box. Select TCP/IP, and then click Properties. The default port number appears in the text box.</li></ol> </li> Add the port number and the virtual IP address of your SQL Server in the Commerce connection string. <ol style="list-style-type: lower-alpha;"> Open Commerce Server Manager.</li> Right-click Commerce Server Manager.</li> Click Properties.</li> In the Commerce Server Manager Properties dialog box, click Modify. This opens the Data Link Properties dialog box.</li> Click the All tab.</li> Select Network Address, and then click Edit Value.</li> Type the virtual IP address of the virtual instance of SQL Server and the port number, separated by a comma. For example, if the virtual IP address of SQL Server is, and it is listening on TCP/IP port number 2433, type the following for Network Address:

,2433

</li></ol> </li></ol>

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STATUS
Microsoft has confirmed that this is a bug in Microsoft SQL Server 2000.

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