Name-in-Conflict Frames Due to Broadcast Name-Recognize Frames

ID: Q124069

The information in this article applies to:

Microsoft LAN Manager, versions 2.2b, 2.2c

SYMPTOMS

Several LAN Manager servers may stop responding (hang), display STOP messages, and log the following error:

SERVER NET5325

The network protocol has detected two or more identical names on the network. The network control block <NCB> is the data.

It is important to immediately get a trace of network traffic. The NET5325 Name-in-Conflict messages are known to occur in some cases with a specific hardware and software combination. The computer that causes this problem initially may have one or more elements of the following configuration:

PS/2 model 77

3c523 etherlink MC network interface card (NIC)

Windows NT version 3.1 or 3.5

NBF and NBT protocols

The first computer to fail begins to operate with a source address of FFFFFFFFFFFF.

Name-Recognize frames should direct back to the station address issuing a Name-Query frame. In this case, when the Name-Recognize frames are directed back to the offending Windows NT workstation whose address has become FFFFFFFFFFFF, the frame becomes a broadcast frame. This causes problems with the LAN Manager clients in that they may erroneously identify remotely attached LAN Manager servers as being in a Name-in-Conflict condition. The LAN Manager Servers identified in this case log a NET5325 error message in their log files and hang.

NOTE: The presence of NET5325 errors in LAN Manager servers is not sufficient in itself to identify this as the same problem (without the trace information noted above). It is common to get NET5325 when a particular workstation name is in use by two computers at the same time on the same network.

To locate the problem computer, search the network trace for a destination address of FFFFFFFFFFFF. (Due to a known problem with Network General this may require searching for FEFFFFFFFFFF on Network General sniffers.) If such a frame is found, the Name-Recognize frames identify the offending computer name as the destination name in the NetBIOS portion of the frame.

When a Name-Recognize frame with a destination address of FFFFFFFFFFFFF is sent over the network, all LAN Manager workstations receive the frame. The following events then occur:

LAN Manager workstation's receiving the frame use the Name-Recognize frame's transmit correlator to identify a remote connection having a corresponding offset in an internal table of remote connections. If a corresponding remote connection is found in the table, the LAN Manager workstation will generate a Name-in-Conflict frame. The NetBIOS destination name will be the remote server's name.

If the remote server is a LAN Manager server, when the Name-in- Conflict frame is received by the server, a NET5325 error log entry will be generated in the LAN Manager error log and the LAN Manager Server hangs.

RESOLUTION

This problem has been fixed by altering NETBEUI.EXE for the LAN Manager workstation. When a LAN Manager workstation recieves a Name-Recognize frame, if the destination addresss is FFFFFFFFFFFF, no Name-in-Conflict messages will be generated.

STATUS

Microsoft has confirmed this to be a problem in LAN Manager version 2.2. A specific fix to this problem for LAN Manager version 2.2 is in development, but has not been regression-tested and may be destabilizing in production environments. Microsoft does not recommend implementing this fix at this time. Contact Microsoft Product Support Services for more information on the availability of this fix.

MORE INFORMATION

Additional query words: adapter prodlm 2.20b 2.20c lm22

Keywords :
Version : :2.2b,2.2c
Platform :
Issue type :