Subject: Re: How to change serial baud rate on already installed bootblocks
To: Job Hanssen <job.hanssen@xs4all.nl>
From: Job Hanssen <job.hanssen@xs4all.nl>
List: port-i386
Date: 09/06/2007 09:03:02
David Laight schreef:
> On Wed, Sep 05, 2007 at 06:43:32PM +0200, Job Hanssen wrote:
>> Problem solved...
>>
>> Suddenly it hit me: I shouldn't have reinstalled the bootblocks on
>> /dev/rdw0a, but on /dev/rdw0d, as this is wat the disklabel looks like:
>>
>> testbak# disklabel /dev/rwd0
>> # /dev/rwd0d:
> ...
>> 13 partitions:
>> # size offset fstype [fsize bsize cpg/sgs]
>> a: 2097152 63 4.2BSD 2048 16384 21848 # (Cyl. 0*-
>> 2080*)
>> b: 8388608 2097215 swap # (Cyl. 2080*-
>> 10402*)
>> c: 488397105 63 unused 0 0 # (Cyl. 0*-
>> 484520)
>> d: 488397168 0 unused 0 0 # (Cyl. 0 -
>> 484520)
> ...
>> testbak# hexdump -x -s0x418 -n4 /dev/rwd0a
>> 0000418 c200 0001
>> testbak# hexdump -x -s0x418 -n4 /dev/rwd0d
>> 0000418 9600 0000
>
> Hmmm... I suspect things have got themselves very confused!
I suspect that _I_ have got things very confused! ;-)
> The disklabel looks like a 'standard' i386 pc config with a single
> type 169 mbr partition covering all but the first track.
> In that case sector zero of the disk would usually contain one of
> /usr/mdec/mbr* files, and sector 63 (ie the first of the mbr partition)
> /usr/mdec/bootxx_xxxfs.
> For various reasons the pbr code does have space for the mbr table,
> so it does all work - but is somewhat confusing - as you found out.
I'm not sure what you mean with pbr code.
Appearently there's no 'real' mbr at the moment:
testbak# fdisk
Disk: /dev/rwd0d
NetBSD disklabel disk geometry:
cylinders: 484521, heads: 16, sectors/track: 63 (1008 sectors/cylinder)
total sectors: 488397168
BIOS disk geometry:
cylinders: 1023, heads: 255, sectors/track: 63 (16065 sectors/cylinder)
total sectors: 488397168
Partition table:
0: <UNUSED>
1: <UNUSED>
2: <UNUSED>
3: <UNUSED>
testbak# disklabel /dev/rwd0
# /dev/rwd0d:
type: ESDI
disk: WDC WD2500JB-00E
label: netbsd
flags:
bytes/sector: 512
sectors/track: 63
tracks/cylinder: 16
sectors/cylinder: 1008
cylinders: 484521
total sectors: 488397168
rpm: 3600
interleave: 1
trackskew: 0
cylinderskew: 0
headswitch: 0 # microseconds
track-to-track seek: 0 # microseconds
drivedata: 0
13 partitions:
# size offset fstype [fsize bsize cpg/sgs]
a: 2097152 63 4.2BSD 2048 16384 21848 # (Cyl. 0*- 2080*)
b: 8388608 2097215 swap # (Cyl. 2080*- 10402*)
c: 488397105 63 unused 0 0 # (Cyl. 0*- 484520)
d: 488397168 0 unused 0 0 # (Cyl. 0 - 484520)
e: 4194304 10485823 4.2BSD 2048 16384 21848 # (Cyl. 10402*- 14563*)
f: 20971520 14680127 4.2BSD 2048 16384 28088 # (Cyl. 14563*- 35368*)
g: 20971520 35651647 4.2BSD 2048 16384 28088 # (Cyl. 35368*- 56173*)
h: 20971520 56623167 4.2BSD 2048 16384 28088 # (Cyl. 56173*- 76978*)
i: 20971520 77594687 4.2BSD 2048 16384 28088 # (Cyl. 76978*- 97783*)
j: 20971520 98566207 4.2BSD 2048 16384 28088 # (Cyl. 97783*- 118589*)
k: 20971520 119537727 4.2BSD 2048 16384 28088 # (Cyl. 118589*- 139394*)
l: 20971520 140509247 4.2BSD 2048 16384 28088 # (Cyl. 139394*- 160199*)
m: 41943040 161480767 4.2BSD 2048 16384 28088 # (Cyl. 160199*- 201809*)
Suppose I were to make this system behave as it's supposed to. How would I go
about it?
- install a new mbr on /dev/rwd0d (using fdisk I suppose?). I suppose I would feed
it with the data from disklabel on partition c as input?
- set the NetBSD-partition as active (also using fdisk)
- (re)install the bootblock on /dev/rwd0a as already discussed in this thread.
Regards,
Job Hanssen