Perfmon and Network Monitor Counters Show Incorrect Values

• Microsoft Windows NT Workstation versions 3.5 and 3.51
• Microsoft Windows NT Server versions 3.5 and 3.51
• Microsoft Systems Management Server versions 1.0 and 1.1

SYMPTOMS

Under heavy stress situations, Windows NT computers running Network Monitor or Performance Monitor on a Token Ring 16Mb network with a NetFlx Eth/TR II network interface card (NIC) return zero for the following performance counters:

   Perfmon Network Segment Object:

      % Broadcast frames
      % Multicast Frames
      % Network utilization
      Broadcast frames received/second
      Multicast frames received/second
      Total bytes received/second

   Network General

      % Broadcast frames
      % Multicast Frames
      % Network utilization
      Broadcast frames received/second
      Multicast frames received/second
      Total bytes received/second

NOTE: The Performance counters do appear after a short period of time to recover as the values start to again increment but they never fully recover in that the values appear extremely low.

CAUSE

The NetFlex II NIC stops responding (hangs) and the counters are reset to 0.

RESOLUTION

This problem has been corrected in the latest Service Pack for Windows NT version 3.51. Windows NT now polls the NIC every 2 seconds to check for a hung condition. If hung, it is reset, but not into promiscuous mode. This problem does not happen when the NIC is running in normal mode.

STATUS

Microsoft has confirmed this to be a problem in Windows NT version 3.51. This problem was corrected in the latest Windows NT 3.51 U.S. Service Pack. For information on obtaining the Service Pack, query on the following word in the Microsoft Knowledge Base (without the spaces):

   S E R V P A C K