On Sat, 09 Apr 2005, Nenad Crnko wrote:

> On 04/08/2005 Oliver Fuchs wrote:
> > 2) Deleting the installed netbsd 1.6.1 system and partitioning the
> > wd1 disk with netbsd 2.0 sysinst I was not able to boot into netbsd
> > 2.0 neither from installed bootselector on wd0 (it gives me the
> > message "no operating system" and then directly "press any key to
> > reboot") nor from the installation cd with boot hd1a:).
> Can you tell us exactly how have you deleted 1.6.1? What commands
> have you used?
> 
> I do recall some difficulties in my embedded system where trivial
> approach would sometimes not be able to to bring an arbitrarily
> badly corrupted disk into a sane state. So I used a brute force of
>   dd if=/dev/zero of=/dev/rwd1d bs=1m count=1
> before creating a new fs. I have not investigated the actual mode
> of failure.

Hi,
I tried nearly everything to delete 1.6.1:
1) I installed netbsd 2.0 directly over it with sysinst (create a
partition that uses the whole disk and use existing partition sizes).
1a) I installed netbsd 2.0 directly over it with sysinst (create a
partition that uses the whole disk and set the partition sizes).
2) deleted the whole disk with partition magic and  formatted it with
fat32
3) Installed another operating system on it and then tried to install
netbsd 2.0 overit
4) delete the partition with DOS FDISK
5) dd if=/dev/zero of=/dev/wd1 count=100 (from the installation shel)
   fidsk wd1

> >> We have missed the opportunity to get the content from wd1 mbr when
> >> your system still failed to boot. It would have been useful to get it
> >> like so:
> >>   # dd if=/dev/wd1d of=/tmp/funny_mbr count=1
> >> or
> >>   # dd if=/dev/wd0d count=1 | hexdump -C
> 
> another typo -------^
> it, of course, should have been wd1d
> >
> >I tried it now (the first one) and it shows me besides others:
> >
> >        Invalid partition table
> >        No operating system
> >        Error loading operating system
> 
> Ok, try reading raw device. This must succeed:
>    # dd if=/dev/rwd1d count=1 of=/tmp/funny_mbr.txt
> 
> Hexdump is probably not available during installation, so you can
> do it later on another machine.

This gives me:
00000000  31 c0 8e d0 66 bc 00 7c  00 00 8e c0 8e d8 89 e6  |1À.Ðf¼.|...À.Ø.æ|
00000010  66 bf 00 06 00 00 66 b9  00 01 00 00 f3 a5 ea 23  |f¿....f¹....ó¥ê#|
00000020  06 00 00 80 fa 80 7c 05  80 fa 87 7e 02 b2 80 88  |....ú.|..ú.~.²..|
00000030  16 4b 07 66 bf be 07 00  00 31 f6 66 b9 04 00 00  |.K.f¿¾...1öf¹...|
00000040  00 67 80 7f 00 80 75 07  85 f6 75 0c 66 89 fe 83  |.g....u..öu.f.þ.|
00000050  c7 10 e2 ed 85 f6 75 0b  66 be 4c 07 00 00 e9 8e  |Ç.âí.öu.f¾L...é.|
00000060  00 00 00 8a 16 4b 07 66  31 c9 66 31 c0 b4 08 cd  |.....K.f1Éf1À´.Í|
00000070  13 c1 ea 08 42 89 c8 83  e0 3f 89 cb c1 e9 08 81  |.Áê.B.È.à?.ËÁé..|
00000080  e3 c0 00 00 00 c1 e3 02  09 d9 41 f7 e2 66 f7 e1  |ãÀ...Áã..ÙA÷âf÷á|
00000090  8a 16 4b 07 66 67 8b 5e  08 66 39 c3 66 7c 64 66  |..K.fg.^.f9Ãf|df|
000000a0  56 52 66 bb aa 55 00 00  b4 41 cd 13 5a 66 5e 72  |VRf»ªU..´AÍ.Zf^r|
000000b0  52 66 b8 55 aa 00 00 39  c3 75 48 f6 c1 01 74 43  |Rf¸Uª..9ÃuHöÁ.tC|
000000c0  67 66 c7 46 00 10 00 01  00 67 66 c7 46 04 00 7c  |gfÇF.....gfÇF..||
000000d0  00 00 67 66 c7 46 0c 00  00 00 00 b6 05 56 52 b4  |..gfÇF.....¶.VR´|
000000e0  42 cd 13 5a 5e 73 45 fe  ce 75 f2 66 be 78 07 00  |BÍ.Z^sEþÎuòf¾x..|
000000f0  00 ac 84 c0 74 0a b4 0e  b3 07 56 cd 10 5e eb f1  |.¬.Àt.´.³.VÍ.^ëñ|
00000100  fb eb fd 67 8a 76 01 67  8b 4e 02 66 bf 05 00 00  |ûëýg.v.g.N.f¿...|
00000110  00 66 bb 00 7c 00 00 66  b8 01 02 00 00 57 52 51  |.f».|..f¸....WRQ|
00000120  cd 13 59 5a 5f 73 05 4f  75 e7 eb bf 66 be 64 07  |Í.YZ_s.Ouçë¿f¾d.|
00000130  00 00 67 a1 fe 7d 00 00  66 bb 55 aa 00 00 39 c3  |..g¡þ}..f»Uª..9Ã|
00000140  75 af 8a 16 4b 07 ea 00  7c 00 00 80 49 6e 76 61  |u¯..K.ê.|...Inva|
00000150  6c 69 64 20 70 61 72 74  69 74 69 6f 6e 20 74 61  |lid partition ta|
00000160  62 6c 65 00 4e 6f 20 6f  70 65 72 61 74 69 6e 67  |ble.No operating|
00000170  20 73 79 73 74 65 6d 00  45 72 72 6f 72 20 6c 6f  | system.Error lo|
00000180  61 64 69 6e 67 20 6f 70  65 72 61 74 69 6e 67 20  |ading operating |
00000190  73 79 73 74 65 6d 00 00  00 00 00 00 00 00 00 00  |system..........|
000001a0  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
000001b0  00 00 00 00 00 00 00 00  fe 3a fa 40 00 00 00 00  |........þ:ú@....|
000001c0  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
*
000001e0  00 00 00 00 00 00 00 00  00 00 00 00 00 00 80 01  |................|
000001f0  01 00 a9 fe ff ff 3f 00  00 00 71 f8 50 09 55 aa  |..©þÿÿ?...qøP.Uª|
00000200

> In order to get a copy of the wd1 mbr, you can probably
> ftp or scp it to another machine, or copy it to a floppy
> or a flash disk. The latter you could do like this:
>  if you have a compact flash:
>    # mount_msdos /dev/sd0e /mnt
>  else if floppy:
>    # mount_msdos /dev/fd0a /mnt
>  endif
> 
>    # dd if=/dev/rwd1d count=1 of=/mnt/funny_mbr
>    # umount /mnt
> 
> If you have another unix machine running sshd you could:
>    # dd if=/dev/rwd1d count=1 of=/tmp/funny_mbr
>    # scp /tmp/funny_mbr.txt IP_of_the_other_machine:/tmp/
> 
> Once you get the file to another machine do:
>    # hexdump -C funny_mbr > funny_mbr.txt
> 
> > But what I do not understand is that I was able to install netbsd
> > 1.6.1 without problems when the disk wd1 was partitioned with FreeBSD
> > 5.3 sysinstall.
> 
> It is not impossible that any bug or problem is only exposed under specific
> circumstances and only in a particular version of software. Bugs that are
> easy to encounter usually do not survive for long in open source software.

Oliver
-- 
.. don't touch the bang bang fruit