Very Computer

Hi all,

My new 2.2.7 box insists on mounting the wrong root disk.
The kernel lives on sd(0,a), the bootloader finds it and
the hardware probe is successful, but when the probe is
complete the kernel then tries to mount sd(1,a) on /.
There is no sd(1,a) and panic ensues 8-)

It's an older Pentium 90, with a Neptune chipset. There is a
single IDE disk attached to the motherboard IDE controller, the
SCSI controller is an NCR 815 carrying sd0 and a NEC cdrom.
The IDE drive carries a win95 installation to which I'd like
to preserve access. The boot manager on wd0 starts the boot
manager of sd0, which then starts the kernel on sd0a; that
part works like a champ.

The installation was by FTP. Plug and Pray has been disabled to
keep the network card going, but turning it on didn't solve
the problem. The motherboard reports an autoconfiguration error
during POST, but that's been present forever and caused no trouble
recognizable with win95. Enabling PnP avoids the POST error but
causes the ethernet card's irq and base address to wander.

It's possible to make the system boot successfully by manually
entering

1:sd(0,a)kernel

at the boot: prompt, but the problem returns
at the next reboot. Why such a command would be needed is a puzzle,
the failure of the boot: -c command to "stick" compounds it.
In other respects the system seems to work fine.

I tried installing with the root disk at SCSI id 1, but that
mount failed too and I chalked it up to the special status of
id 0. Now I'm not so sure, and I'll admit so some uncertainty
about which (sd0 or sd1) device was treated as the root device
in that attempt. Building a new kernel with "root on sd0"
didn't help.

The present configuration seems reasonable and ought to work.
If anybody has a suggestion I'd very much appreciate it. At
this point the system is good only to the next power outage.

thanks for reading!

bob

Quote:> It's possible to make the system boot successfully by manually
> entering

> 1:sd(0,a)kernel

> at the boot: prompt, but the problem returns at the next reboot.

Great.  Boot this way and put that string into /boot.config;
next time the bootloader will take it automagically.

Quote:> Why such a command would be needed is a puzzle,

Well, the boot loader is unfortunately dependent on the BIOS to
load the kernel.

Quote:> the failure of the boot: -c command to "stick" compounds it.

The "boot -c" is triggering code inside the kernel which is
setting some flags and parameter inside the kernel file.

Quote:> Now I'm not so sure, and I'll admit so some uncertainty
> about which (sd0 or sd1) device was treated as the root device

Well, the disk with the lowest SCSI-id will become sd0.  The device
number is not directly related to the SCSI-id unless you hardwire
it in the kernel.

HTH,
                                Ripley
--
http://www.in-berlin.de/User/nostromo/
==
"You don't say what kind of CD drive or hard disks you have, but since it is
causing you trouble I'll assume it is IDE."  -- comp.unix.bsd.freebsd.misc

Thank you Ripley!! it  worked like a charm.

There is one other small puzzle. If I understand the prompts
correctly, at the boot: prompt I could in principle also enter
1:sd(0,a)kernel -r  to _force_ a reassignment of the default
boot disk, partition and filename. When I attempt this, the
system gets farther, successfully fscking all the partitions,
but failing to mount root saying the filesystem types don't match.

Any idea what' going on? It seems as if the bios and disk
disagree about something, but I don't know what.

thanks for your help!!!

bob