New 802.2 Connections Always Appear as Ethernet in SNA Manager (288842)

SYMPTOMS

If you add new Data Link Control (DLC) 802.2 link services to an SNA Server configuration after you apply SNA Server 4.0 Service Pack 4 (SP4), all connections that use these link services appear to be Ethernet connections even if Token Ring adapters are being used for the physical connection.

The new connections have an Ethernet icon (T-shaped tap) when the connections are viewed in SNA Server Manager. The Connection Properties dialog box in Manager also indicate that the connection type is Ethernet.

NOTE: New connections that are created after you apply SNA Server 4.0 SP4 show the correct network icon if they are configured to use DLC 802.2 link services that were installed before SP4.

CAUSE

When you install SNA Server 4.0 SP4 on Windows NT 4.0, SNA Server 4.0 SP4 does not correctly read the installed network adapter's MediaType registry parameter. Therefore, all DLC 802.2 connections appear as Ethernet connections because this is the default connection type in SNA Server.

SNA Server 4.0 SP3 and SP4 display all DLC 802.2 connections as Ethernet connections on Windows 2000 because the MediaType registry entry does not exist in Windows 2000. Therefore, the default connection type of Ethernet is always used when installing SNA Server 4.0 SP3 and SP4 on Windows 2000.

RESOLUTION

A supported fix is now available from Microsoft, but it is only intended to correct the problem that is described in this article. Apply it only to computers that are experiencing this specific problem. This fix may receive additional testing. Therefore, if you are not severely affected by this problem, Microsoft recommends that you wait for the next Microsoft SNA Server version 4.0 service pack that contains this hotfix.

To resolve this problem immediately, contact Microsoft Product Support Services to obtain the fix. For a complete list of Microsoft Product Support Services phone numbers and information about support costs, visit the following Microsoft Web site:

http://support.microsoft.com/default.aspx?scid=fh;EN-US;CNTACTMS

NOTE: In special cases, charges that are ordinarily incurred for support calls may be canceled if a Microsoft Support Professional determines that a specific update will resolve your problem. The typical support costs will apply to additional support questions and issues that do not qualify for the specific update in question.

The English version of this fix has the file attributes (or later) that are listed in the following table. The dates and times for these files are listed in coordinated universal time (UTC). When you view the file information, it is converted to local time. To find the difference between UTC and local time, use the Time Zone tab in the Date and Time tool in Control Panel.

File name	Date	Time
Snarpccl.dll	03/05/2001	09:25AM
Snarpcsv.exe	03/05/2001	09:26AM

NOTE: Because of file dependencies, the most recent fix that contains the preceding files may also contain additional files.

MORE INFORMATION

After you apply the fix, use one of the following procedures, depending on whether the SNA Server configuration includes connections with the incorrect Ethernet icon:

If the SNA Server does not have any installed DLC 802.2 link services configured to use the Token Ring adapter and there are no connections that show the incorrect Ethernet icon, add new DLC 802.2 link services. New connections that use these newly added link services will show the correct Token Ring connection icon.

-or-
If the SNA Server configuration has current connections with the wrong connection icon, follow these steps:
1. Delete the DLC 802.2 link services (SnaDlc1) that the connections with the incorrect icon are using.
  
  NOTE: Removing the link services will cause any existing connections that were using it to show a link service of <None> when you view the connection's Properties in SNA Manager.
2. Save the configuration.
3. Add DLC 802.2 link services that point to the Token Ring adapter.
4. Open the affected connections and select a DLC 802.2 link service that was just added in step c.
5. Save the configuration.
6. Close and re-open SNA Manager. The connections should now show the correct Token Ring icon.

For additional information about a similar problem and how to determine the SNA Server DLC 802.2 connection type, click the article number below to view the article in the Microsoft Knowledge Base:

140149 SNA 802.2 Connection Icon Indicates Incorrect Network Type

Because the MediaType registry parameter is not available in Windows 2000, the DLC 802.2 link service was changed in Host Integration Server 2000 to query DLC to determine the network adapter's media type. This change to query DLC was included in this fix so that the correct media type is determined when you run SNA Server 4.0 SP4 on Windows 2000 after the fix is applied.

If you install SNA Server or Host Integration Server 2000 on Windows NT 4.0, the updated DLC 802.2 link service still reads the MediaType registry parameter to determine the connection type.

The maximum Basic Transmission Unit (BTU) length for Ethernet connections defaults to 1493, whereas the default for Token Ring connections is 1929. The problem described here could result in some network connectivity issues because of the difference in the default maximum BTU length.

For additional information about how SNA Server determines the maximum BTU length over the 802.2 DLC connection, click the article number below to view the article in the Microsoft Knowledge Base: