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Date:      Mon, 1 Aug 2005 13:56:25 +0200
From:      vdm.fbsd@virgilio.it
To:        freebsd-questions@freebsd.org
Cc:        Glenn Dawson <glenn@antimatter.net>
Subject:   Re: Problems with booting & MBR
Message-ID:  <42DC14FE0005267F@ims1d.cp.tin.it>
In-Reply-To: <6.1.0.6.2.20050729083038.116d2d80@cobalt.antimatter.net>

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Dear Glenn,
even though a bit late here you are the info you suggested to check (stil=
l
absolutely obscure to me!!):

Yes, the / directory for booting is /dev/ad1s2a as in the fstab file.

>From dmesg:
ad0: 9541MB <WDC WD100BA/16.13M16> [19386/16/63] at ata0-master UDMA33
ad1: 9541MB <WDC WD200EB-11CPF0/06.04G06> [19386/16/63] at ata0-slave UDM=
A33

vicbsd root# fdisk /dev/ad0
******* Working on device /dev/ad0 *******
parameters extracted from in-core disklabel are:
cylinders=3D19386 heads=3D16 sectors/track=3D63 (1008 blks/cyl)

Figures below won't work with BIOS for partitions not in cyl 1
parameters to be used for BIOS calculations are:
cylinders=3D19386 heads=3D16 sectors/track=3D63 (1008 blks/cyl)

Media sector size is 512
Warning: BIOS sector numbering starts with sector 1
Information from DOS bootblock is:
The data for partition 1 is:
sysid 165 (0xa5),(FreeBSD/NetBSD/386BSD)
    start 63, size 19541025 (9541 Meg), flag 80 (active)
        beg: cyl 0/ head 1/ sector 1;
        end: cyl 1023/ head 15/ sector 63
The data for partition 2 is:
<UNUSED>
The data for partition 3 is:
<UNUSED>
The data for partition 4 is:
<UNUSED>

vicbsd root# fdisk /dev/ad1
******* Working on device /dev/ad1 *******
parameters extracted from in-core disklabel are:
cylinders=3D19386 heads=3D16 sectors/track=3D63 (1008 blks/cyl)

Figures below won't work with BIOS for partitions not in cyl 1
parameters to be used for BIOS calculations are:
cylinders=3D19386 heads=3D16 sectors/track=3D63 (1008 blks/cyl)

Media sector size is 512
Warning: BIOS sector numbering starts with sector 1
Information from DOS bootblock is:
The data for partition 1 is:
<UNUSED>
The data for partition 2 is:
sysid 165 (0xa5),(FreeBSD/NetBSD/386BSD)
    start 9179856, size 10361232 (5059 Meg), flag 80 (active)
        beg: cyl 1023/ head 15/ sector 63;
        end: cyl 1023/ head 15/ sector 63
The data for partition 3 is:
<UNUSED>
The data for partition 4 is:
<UNUSED>
                                                                        
      
vicbsd root# bsdlabel /dev/ad1s2
# /dev/ad1s2:
8 partitions:
#        size   offset    fstype   [fsize bsize bps/cpg]
  a:  9312656  1048576    4.2BSD     2048 16384 28552
  b:  1048576        0      swap
  c: 10361232        0    unused        0     0         # "raw" part, don=
't
edit

vicbsd root# bsdlabel /dev/ad0s1
# /dev/ad0s1:
8 partitions:
#        size   offset    fstype   [fsize bsize bps/cpg]
  a: 14336000        0    4.2BSD        0     0     0
  b:  1084449 18456576      swap
  c: 19541025        0    unused        0     0         # "raw" part, don=
't
edit
  d:   524288 14336000    4.2BSD     2048 16384 32776
  e:   524288 14860288    4.2BSD     2048 16384 32776
  f:  3072000 15384576    4.2BSD     2048 16384 28552


Ciao
Vittorio
>-- Messaggio originale --
>Date: Fri, 29 Jul 2005 08:43:10 -0700
>To: Vittorio De Martino <vdm.fbsd@virgilio.it>
>From: Glenn Dawson <glenn@antimatter.net>
>Subject: Re: Problems with booting & MBR
>
>
>At 08:25 AM 7/29/2005, you wrote:
>>Friends,
>>as suggested in the docs in the internet I tried both with
>> 
>>
>># fdisk -B -b /boot/boot0 ad0
>>fdisk: cannot open disk /dev/ad0: No such file or directory
>>
>>and with
>> 
>>
>># fdisk -B -b /boot/boot0 ad1
>>fdisk: cannot open disk /dev/ad1: No such file or directory
>>
>>WHILST
>>my working /etc/fstab is, as I mentioned before:
>># Device                Mountpoint      FStype  Options         Dump  

>Pass#
>>/dev/ad1s2b             none            swap    sw              0     

>0
>>/dev/ad1s2a             /               ufs     rw              1     

>1
>>/dev/ad0s1a             /usr/local      ufs     rw              0     

>0
>>/dev/ad0s1d             /var            ufs     rw              0     

>0
>>/dev/ad0s1e             /tmp            ufs     rw              0     

>0
>>
>>Why FreeBSD 5.4 cannot find /dev/ad0 and ad1?
>>What should I do?
>
>How are you booting the system to get to a prompt where you can issue th=
e
>
>commands shown above?
>
>The first thing you probably need to do is examine dmesg output and see

>what disk devices are being detected at boot time.  Then look in /dev an=
d
>
>see if the entries you need are there or not.
>
>Also, one thing to keep in mind is that the bootloader only knows how to=

>
>find the root file system when it's on the 'a' partition.  Based on your=

>
>fstab above, that would be /dev/ad1s2a.  Assuming that's correct, what's=

>on 
>ad1s1?
>
>It would be helpful to see output from 'fdisk /dev/ad0' and 'fdisk 
>/dev/ad1' if you can get it.  Then depending on what slices are there, t=
he
>
>corresponding bsdlabel output.  Here's a sample from one of my test syst=
ems
>
>(it boots from /dev/ad4 which has two slices, one with 4.11 and one with=

>
>5.4 installed)
>
>test54# fdisk /dev/ad4
>******* Working on device /dev/ad4 *******
>parameters extracted from in-core disklabel are:
>cylinders=3D387621 heads=3D16 sectors/track=3D63 (1008 blks/cyl)
>
>Figures below won't work with BIOS for partitions not in cyl 1
>parameters to be used for BIOS calculations are:
>cylinders=3D387621 heads=3D16 sectors/track=3D63 (1008 blks/cyl)
>
>Media sector size is 512
>Warning: BIOS sector numbering starts with sector 1
>Information from DOS bootblock is:
>The data for partition 1 is:
>sysid 165 (0xa5),(FreeBSD/NetBSD/386BSD)
>     start 63, size 10474317 (5114 Meg), flag 80 (active)
>         beg: cyl 0/ head 1/ sector 1;
>         end: cyl 651/ head 254/ sector 63
>The data for partition 2 is:
>sysid 165 (0xa5),(FreeBSD/NetBSD/386BSD)
>     start 10474380, size 10458315 (5106 Meg), flag 0
>         beg: cyl 652/ head 0/ sector 1;
>         end: cyl 1023/ head 254/ sector 63
>The data for partition 3 is:
><UNUSED>
>The data for partition 4 is:
><UNUSED>
>
>And, the bsdlabel output from the two slices that are shown above:
>
>test54# bsdlabel /dev/ad4s1
># /dev/ad4s1:
>8 partitions:
>#        size   offset    fstype   [fsize bsize bps/cpg]
>   a:   524288        0    4.2BSD     2048 16384 32776
>   b:  2038416   524288      swap
>   c: 10474317        0    unused        0     0         # "raw" part, 
>don't edit
>   d:   524288  2562704    4.2BSD     2048 16384 32776
>   e:   524288  3086992    4.2BSD     2048 16384 32776
>   f:  6863037  3611280    4.2BSD     2048 16384 28552
>
>
>test54# bsdlabel /dev/ad4s2
># /dev/ad4s2:
>8 partitions:
>#        size   offset    fstype   [fsize bsize bps/cpg]
>   a:   262144        0    4.2BSD        0     0     0
>   c: 10458315        0    unused        0     0         # "raw" part, 
>don't edit
>   e:   524288   262144    4.2BSD        0     0     0
>   f:   524288   786432    4.2BSD        0     0     0
>   g:  9147595  1310720    4.2BSD        0     0     0
>
>
>Once you know where things actually are on the disks you have, it'll be
a
>
>lot easier to figure out what needs to be done in order to have it boot

>correctly.
>
>-Glenn
>
>
>
>
>>A baffled and frustated Vittorio again
>>_______________________________________________
>>freebsd-questions@freebsd.org mailing list
>>http://lists.freebsd.org/mailman/listinfo/freebsd-questions
>>To unsubscribe, send any mail to "freebsd-questions-unsubscribe@freebsd=
.org"
>





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