SCO UNIX driver initializes 3C509 by Ethernet address

Problem: The SCO UNIX driver initializes 3C509 cards in ascending order by Ethernet address irrespective of the configured order.

Solution: This problem is described in the 3Com Etherlink III Driver for SCO UNIX Release and Installation Notes under the section titled "Configuring the EtherLink III Driver". To quote:

"For the EtherLink III ISA adapter (3C509), device e3E0 will always be associated with the adapter with the lowest Ethernet address, device e3E1 with the adapter with the next lowest, etc. This is true even in the case where an adapter is added to an existing configuration. If the adapter being added has a lower Ethernet address than any of the adapters already installed, the device names of the existing adapters will change so that the devices are in Ethernet address order."

SCO's LLI driver doc states the same but much better:

Installing multiple 3C509 EtherLink III adapters:

When you install multiple EtherLink III adapters the 3C509 driver assigns the I/O base addresses you select in an order based on the adapters' Ethernet addresses. Therefore, you must follow these steps to be able to identify individual adapters with their respective transport interfaces:

1. Note each adapter's Ethernet address. The Ethernet address is stamped on the top of your adapter near the bar code and should be similar to the following:

EA=00608CBBA74D

2. The first driver name, e3E0, is assigned by the driver to the Ethernet address with the lowest hexidecimal value. Subsequent driver names are assigned to Ethernet addresses in ascending hexidecimal value order, following the driver naming convention described in the ``Driver name'' section above. We recommend that you label the back plate of each adapter to aid you in making network cable connections.

3. When you run netconfig, configure chains of networking products using the assigned driver names.

CAUTION If you subsequently install an additional 3C509 adapter that has a lower Ethernet address than the existing adapters, you must physically reconnect your network cables based on the new ordering.