I have here a hp300 system (hp9000/425) on which I wanted to
do a fresh NetBSD install.

However, I don't have any other NetBSD machine available, which
made things a bit more difficult (or then I just made things in
a difficult way).

I do have a Linux system to use as a helper, though - so what
I ended up doing was:
- set up rbootd on Linux

  see: http://www.chiark.greenend.org.uk/~pmaydell/hp/

- set up the Linux system (SuSE 9.3, with 2.6.11.4-21.12 kernel) as
  NFS server and bootp/dhcp server, providing root file system
  (with base and etc filesets) and swap area for diskless booting
  
  see:
  - http://www.netbsd.org/Documentation/network/netboot/dhcpd.html
  - http://www.netbsd.org/Documentation/network/netboot/nfs.html

  This version of Linux appears to have the NFS layer working - or
  at least I didn't get any unpleasant surprises. I also copied over
  the SYS_INST boot image and miniroot image into the exported
  directory, to have them available for the client.

- boot the "diskless" system from the above set-up

- clear out the installed disk (just to be sure)
  dd if=/dev/zero of=/dev/sd0c bs=512 count=1024

- label the disk
  disklabel -e -I sd0

  notes:
  - offset of sd0a needs to be 200 sectors, to leave room for boot code,
    as described in
    ftp://ftp.netbsd.org/pub/NetBSD/NetBSD-3.0/hp300/INSTALL.html#Designing%20your%20disk's%20partition%20table
  - swap partition type can be 4.2BSD for now

- make the disk bootable
  disklabel -B -b /path/to/SYS_INST sd0

- copy miniroot image over to sd0b (swap partition)
  dd if=/path/to/miniroot of=/dev/sd0b obs=512

- reset system, boot from SYS_INST on local disk
  notes:
  - install.md on miniroot needs a correction, thus
    root-fs (miniroot) needs to be remounted read-write;
    for the correction see my other message on port-hp300
    mailing list
  - no need to label the disk any more

- install and enjoy


The non-availability of X server was a disappointment, though.
Hopefully this sees some improvement in the future.
-- 
Wolf  a.k.a.  Juha Laiho     Espoo, Finland
(GC 3.0) GIT d- s+: a C++ ULSH++++$ P++@ L+++ E- W+$@ N++ !K w !O !M V
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"...cancel my subscription to the resurrection!" (Jim Morrison)