I have a Compaq dual port NIC card (or two separate NICs), which I
          want to run as a redundant pair so that if the active one fails, the
          other can take over giving network card fault tolerance.

          This is supported by the software within the Compaq EFS and is not
          part of the OpenServer 5 product.  It is specific to Compaq NICs and
          cannot be used with other network cards.  SCO Open UNIX 8 and
          UnixWare 7 give a more card-generic form of NIC failover redundancy.

          The Compaq EFS for OpenServer 5 should be installed (available from
          the Compaq SmartStart CD or from their website).  This software is
          installed using the SCOadmin Software Manager.

          During installation the EFS will prompt to allow configuration of
          any Compaq network cards in the system not currently configured.
          This configuration can be done now or can be done later using the
          "netconfig" utility.  If configured now, you should select to
          configure the cards you wish to run as a redundant pair, add TCP/IP
          networking to one of them (entering IP address, netmask and broadcast
          as prompted).

          When prompted to configure the second Compaq NIC of the redundant
          pair choose to configure the card but do not add the TCP/IP
          protocol to it. Instead, follow the prompts to have the Compaq NIC
          stub driver added.  This will leave the card configured, but with no
          protocol on it making it a candidate for a redundant pair binding
          with the first NIC.

          If this configuration is carried out after installing the EFS, use
          "netconfig" as usual to add and configure TCP/IP on the first NIC and
          add the second with the Compaq stub driver on it.

          Note: when "netconfig" automatically detects the network cards it
          may list the Intel drivers instead of the Compaq drivers, which are
          based on Intel's drivers. If you click on the "Configure hardware not
          listed above", you should be able to find the Compaq drivers within
          the list.  While it is possible to run a Compaq Intel based chipset
          NIC with the Intel driver, you can only use the redundant pair
          functionality with the Compaq driver.

          Once you have one Compaq NIC with TCP/IP configured on it and another
          with the Compaq NIC stub driver configured within netconfig (and
          after relinking the kernel and rebooting as prompted) then you can
          use the Compaq Network Interface Manager "/etc/cpqnim" utility to
          configure the cards as a redundant NIC pair.

          Run "cpqnim" either in the GUI or from a character session and select
          the option for the model of Compaq NICs that are installed, then
          take the following steps:

          - Highlight the first NIC which was configured with the TCP/IP
            protocol earlier.

          - Select from the menu Configuration -> Bind Redundant Pair

          - In the next window, highlight the NIC which was previously
            configured with the Compaq NIC stub driver and select OK.

          The cards should now be linked as a redundant pair (the cpqnim
          manager will show them with an additional link on the right hand
          side and one of them marked as "active").

          Both NICs should be cabled to the same physical subnet.

          NIC failover can be tested by removing the physical network cable
          connection from one of the cards.  The driver should detect link
          lost from the appropriate card and, if that card was active, then
          the redundant card will be marked as "active".  When the link is
          restored this is detected but the current active card will remain
          active until its link fails.  To restore the original link you must
          remove the cable from the redundant card and replace the original
          cable.

          The redundant cards MAC address is reprogrammed to that of the
          primary card as part of this failover so the ARP cache on clients
          can remain unchanged.  New connections will be made to the newly
          active card and existing connections (telnet session, for example)
          will continue without interruption during this failover process.

          Cards which support this feature are as follows:

            - Compaq Netflex-3/Netelligent (cnet driver)
            - Compaq Ethernet/FastEthernet (n100c driver)
            - Compaq Gigabit Controller (n1000c driver)

          Compaq EFS documentation.