                                                             Last Revised
    AST RESEARCH, INC.        TECHNICAL BULLETIN # 1787          12/16/97

    TITLE:  Bravo MS and Managed Hubs

    ISSUE

       Some Bravo MS workstations may not be able to connect to a server
       when using the onboard Intel Pro 100B network adapter directly
       connected to a managed hub.

       This issue may affect the following systems: 503246, 503247,
       503250, 503251, 503320, 503321, 503322, 503323, 503417, and
       503418.

       This issue may also affect any system using an Intel Pro 100B
       network card.

    BACKGROUND

       A managed hub has the capability of supporting different
       configurations on individual ports. These settings must match the
       same settings on the workstation network card in order to
       function properly.

       For example: A Chipcom Oncore 17 port hub could have different
       settings between  2 of the 17 ports, causing only certain
       workstations to connect.

       Each individual port could have different settings for the
       following  port configurations: Alert filter, Port connector,
       network dip setting, link integrity, or auto polarity.

       In order to function correctly, these settings would have to be
       configured to match the settings of the workstation network card.

       The most common configuration problem is whether link integrity
       is ENABLED or DISABLED. If the link integrity setting does not
       match the network card, the workstation will not be able to
       connect to the server. The link signal is sent by the transmitter
       electronics when the cable is not in use. If no Link Integrity
       Test is received, the Link is assumed to be lost.

    ACTION

       Configure the onboard Intel Pro 100B card to a speed of 10MB/sec
       and half-duplex mode using the following steps:

       1. Under Windows 95, double-click My Compute.

       2. Double-click the Control Panel icon under My Computer.

       3. Double-click the Network icon under Control Panel.

       4. Under the configuration tab, double-click the Intel
          EtherExpress Pro/100 setting. This will bring up the
          properties of the Intel card.

       5. Click the Advanced tab and select Duplex Mode in the
          Property Box, then click on the arrow in the Value
          field and select Half-Duplex.

       6. Under the same Advanced tab, select Speed in the
          Property Box, then click the arrow in the Value field
          and select 10MB/sec.

       7. Click OK when finished, which will bring the network
          properties screen back up.

       8. Click OK to close the network properties box.

       9. Shut down and restart system.

       Also configure the managed hub ports to have Link Integrity
       ENABLED. This setting matches the Intel Pro 100B network card
       default configuration that cannot be changed.

       The port configuration is usually performed through a Telnet
       connection.

       Refer to the hub manufacturer documentation for configuration
       procedures.

    NOTES

       N/A

    TAN TPR 152TR

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