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[forsyth@minster.york.ac.uk forsyth@minster.york.ac.uk]

>> Has anyone ported the plan9 file server to a PC?
>> thanks
>> sean quinlan

i did that a few months ago.  it only supports ISA at the moment
(i haven't got an EISA yet to try), and thus only 16 Mbytes
since i don't compensate for the limitations of the pc's DMA addressing.
(it wouldn't be too hard: the SCSI adapter could allocate some
space below 16meg and copy the data; whether that's sensible
is another matter.)

i run the file server on a 16Mb 486sx33 with an Ultrastor 14F
and two Fujitsu SCSI-2 drives.  (it boots from a floppy.)
the ethernets supported are those supported by the cpu/terminal kernel
and also NE2100 clones, which use the AMD Lance
(another device with addressing problems!).
the 486sx33 serves a 486dx2-66 CPU server and a few terminals.
i can't compare its performance to an SS2; i improvised
a bootstrap for Plan 9 that went straight to the pc via 9sscd.

the only host adapter supported is the Ultrastor 14F.  the driver should
work with the 34F with at most minor changes, if any, but my 34F
and not-quite-VESA motherboard don't agree, so i haven't been able to test it.
a bus-mastering VESA device can avoid the 16Mb DMA restrictions, however,
making an ISA/VESA pc more useful as a file server.
i have an Adaptec 1542B/Bustek 542B driver, but it doesn't drive discs
(it runs the 1542B in target mode, not initiator mode);
still, most of what is required is there.