Promiscous Mode Madge Token Ring NIC Can Halt Mainframe Connection

• Microsoft Windows NT Server versions 3.5, 3.51, 4.0
• Microsoft Windows NT Workstation versions 3.5, 3.51, 4.0
• Microsoft Windows NT Server, Enterprise Edition version 4.0
• Microsoft Windows 95

SYMPTOMS

When Microsoft Systems Management Server Network Monitor (Netmon) is running on a token ring segment, mainframe clients on that segment may no longer be able to access or connect to a mainframe host computer. As soon as Netmon is started on a client of a mainframe somewhere in the Token Ring network, all new sessions to the mainframe will fail and the mainframe becomes unavailable to all clients on the token ring network.

CAUSE

The computer (running either Windows NT 4.0 or Windows 95) on which Netmon is running has a Madge PCI Ringnode Token Ring network interface card (NIC) with Mdgmport.sys of version 5.02. When this adapter is set in Promiscuous mode (required for Netmon to monitor all network traffic), the driver will actually de-insert LLC XID frames from the ring.

RESOLUTION

To resolve this problem, upgrade the Madge NIC driver from to 6.0 or newer.

MORE INFORMATION

The third-party products discussed here are manufactured by vendors independent of Microsoft; we make no warranty, implied or otherwise, regarding these products' performance or reliability.

Additional query words: netmon madge ringnode pci token ring pmode promiscuous XID mdgmport miniport

Keywords : kb3rdparty kbhw
Version : WINDOWS:95; winnt:3.5,3.51,4.0
Platform : WINDOWS winnt
Issue type : kbprb