Re: AHA-2940UW Nightmares (Apparently ext2fs errors ?)

Richard B. Johnson (
Thu, 30 Jan 1997 21:31:18 -0500 (EST)

On Thu, 30 Jan 1997, Marco Bravi wrote:

> Dear Linuxers,
> I have been happily using an AHA-2940 with a SCSI and DAT streamer for
> quite a while in a computer room at my Dept. After such a nice experience
> I bought two AHA-2940UW and two SEAGATE ST32155W (2 GB).
> I replaced the old (2940) card with the new (2940UW) one and simply
> appended one of the two new disks. The card was correctly initialized (see
> kernel-related syslog later); I low-level formatted the disk, partitioned
> it with only one file system and high-level formatted it as ext2.


Yes, I recently encountered the same problem. First, If all all possible,
to save your file-system _DO_NOT_ repair with fsck on the new controller
YET. If you do this, you will CREATE inrecoverable errors.

o Reinstall your previous SCSI controller.
o Reboot your machine.
o Copy each file system to the tape:
Like : root file-system

# cd /
# tar -clf /dev/tape . # or whatever its name is

Change tape, don't try to append. It isn't worth the trouble.

# cd /next/file_system
# tar -clf /dev/tape . # or whatever its name is

o After you've got everything..........
o Shutdown and reinstall your new controller.
o Boot on a Distribution disk and CDROM (any verson that has
your new SCSI controller driver).
If you don't have a distribution disk and CDROM, you can
make a root system on a floppy BEFORE you change controllers.
You need /bin/bash (sysinit will find it if init is gone)
symlink /bin/bash to /bin/sh
/dev/everything (tar it over)
/sbin/e2fsk (for an e2 file system)
/sbin/mke2fs ""
/bin/ls (bash will work)
/mnt (empty directory)
/etc (empty directory)

You also need /lib/ and the 'C' runtime libraries
that the above files were linked to.
You build this on a second floppy, before you remove your
old SCSI controller. If you make a bootable floppy, that
mounts a /dev/fd0 file-system, it will prompt you for
the root fs after it gets started.
It may take you the better part of a day getting everything
working on the floppy root-fs.
The command to mount the floppy R/W once the system is up
# /sbin/mount -n -o remount /

o Also make a boot floppy that will mount your SCSI disk root
file system.

Once you have a known good root-fs on a floppy, you
install your new controller and....

o Make new file-systems on your disk partitions...
# mke2fs /dev/whatever (for each file-system)
# mount /dev/whatever /mnt
# cd /mnt
# tar -xpf /dev/tape .
# umount /mnt

o You should NOT have to execute fdisk. You can verify this
before you build a new file-system, by mounting the old and
executing fdisk from it. If fdisk doesn't complain about
the paritions, it's fine.

o You do this for each file system.
o After the last file-system is restored and unmounted,
reboot with the floppy that mounts the new SCSI root file-system.
o Execute lilo to make the new root bootable.

All this stuff is necessary if you change your SCSI controller. This
is because different controllers make different logical-to-physical
translations of the "sectors".

Dick Johnson
Richard B. Johnson
Project Engineer
Analogic Corporation
Voice : (508) 977-3000 ext. 3754
Fax : (508) 532-6097
Modem : (508) 977-6870
Ftp :
Email :,
Penguin : Linux version 2.1.23 on an i586 machine (66.15 BogoMips).
Warning : It's hard to remain at the trailing edge of technology.