SS4 upgrade to 10 - fail to boot miniroot

Hi,

with keyboard and display attached, I try to upgrade the SS4 using the 
miniroot and swap method.

As per guide:

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#*gunzip miniroot.fs.gz*
#*dd if=miniroot.fs of=/dev/rsd0b bs=4k Then I do, as per guide: *|

*boot disk:b netbsd -s Is -s correct? *|

but I get a "short disk read"

While booting in 9.3, I have:
# /dev/rsd0:
type: unknown
disk: sd
label: fictious
flags:
bytes/sector: 512
sectors/track: 186
tracks/cylinder: 8
sectors/cylinder: 1488
cylinders: 5720
total sectors: 8515173
rpm: 3600
interleave: 1
trackskew: 0
cylinderskew: 0
headswitch: 0           # microseconds
track-to-track seek: 0  # microseconds
drivedata: 0

3 partitions:
#        size    offset     fstype [fsize bsize cpg/sgs]
  a:   7465253         0     4.2BSD      0     0     0  # (Cyl.      0 -   5016*)
  b:   1049040   7465296       swap                     # (Cyl.   5017 -   5721)
  c:   8515173         0     unused      0     0        # (Cyl.      0 -   5722*)


so a very easy setup and should match the instruction, what am I overseeing? I hope not a bug :)

Thanks,
Riccardo

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