Hi,

I am tired and about to go to bed, but since the US folks are up and awake
you may want to take a quick look at the problem I had.

I started with my 4/3xx server (dumpty.wonderland.org) and decided
to try to upgrade it to a SS10 I had "lying around" :)

I did exactly two things. Updated the boot blocks with current
using the -h flag to not strip the header (any chance of a converse
flag for moving back ?) and putting a new kernel into place.

Once I addressed the immediate issue of SCSI cable lengths and the
system started booting, most things seemed fine. Boot to single
user worked.

Then... try mountiong for write :(

The three disks (now on a sun4c):

scsibus0 at esp0
probe(esp0:0:0): max sync rate 4.03Mb/s
sd1 at scsibus0 targ 0 lun 0: <DEC, DSP5200S, T392> SCSI2 0/direct fixed
sd1: 1908MB, 2621 cyl, 21 head, 71 sec, 512 bytes/sec
probe(esp0:2:0): max sync rate 4.03Mb/s
sd2 at scsibus0 targ 2 lun 0: <DEC, DSP5200S, T392> SCSI2 0/direct fixed
sd2: 1908MB, 2621 cyl, 21 head, 71 sec, 512 bytes/sec
probe(esp0:3:0): max sync rate 4.03Mb/s
sd0 at scsibus0 targ 3 lun 0: <MAXTOR, LXT-213S, 4.18> SCSI1 0/direct fixed
sd0: 202MB, 1310 cyl, 7 head, 45 sec, 512 bytes/sec

This looks fine. Doing this on the sun4m with the fast SCSI support and the
SCSI1 Maxtro (which we should all know is *not* fast SCSI capable) gets
negotiated to run at 8.06Mb/sec. Ouch. While the two DEC drives are happy at
10Mb/sec sync rate, the Maxtor dies on any writes. (Not suprising).

As I mentioned sleep, I have not looked at the driver code, but
there appears to be no check for fast/slow SCSI and the x2 multiplier.
In these cases, esp when your system is in bits everywhere and you
have no hope of compiling a kernel, a "safe" modem (like Windross
'95) would be really useful :)

'nuff for now - I expect I will investigate further, this weekend,
but if anyone knows a real solution please feel free.

A send-pr will likely follow another day.

-- 
Peter Galbavy                                           peter@wonderland.org
@ Home                                                 phone://44/973/499465
in Wonderland                              http://www.wonderland.org/~peter/
                               snail://UK/NW1_6LE/London/21_Harewood_Avenue/