Section header sez all - you want to use Cardbus adapters for the sake of performance. The PC adapter should support it too. There are numerous 5.25 form factor adapters - input welcome!
This section was inspired by Alan Robertson.
The PCMCIA info was taken from the file
pcmcia-cs-3.0.3/SUPPORTED.CARDS.
Using Fast Ethernet should be straightforward. According to the PCMCIA package documentation, the following 100baseT cards are supported:
[3c574_cs driver]
3Com 3c574TX
[3c575_cb driver]
3Com 3c575TX CardBus
[pcnet_cs driver]
Linksys EtherFast 10/100
[xirc2ps_cs driver]
Intel EtherExpress PRO/100
Xircom CreditCard CE3
I have currently no idea whether any of the supported SCSI cards is FWD but I'm gathering input. Any input welcome, as well as on the question whether any of these cards supports disabling internal SCSI termination for twin-tailing external disk arrays. David Hinds, the maintainer of the PCMCIA package, says "I'm pretty sure that all these cards require external terminators." Fine!
There is at least one Ultra Wide PC Card adapter: the Adaptec SlimSCSIŽ 1480. It does not provide differential SCSI, though, and it is limited to 3 SCSI peripherals in Ultra SCSI mode, and the max cable length for single-ended Ultra SCSI is 1.5 meters. Not a lot for a highly available solution... means the servers have to sit side by side.
Maybe we can use single ended to differential converters in addition to the SCSI adapters. Seems these devices are quite expensive. Any comment welcome.