Well, a very kind soul loaned me an install CD that is very close to the version that is installed (4.0F CD vs. 4.0E installation).
I've been able to boot the CD and get a UNIX shell, and then:
cd /dev
./MAKEDEV re0
disklabel -r re0
Due to my failed attempt to use NetBSD to 'dd' a repaired partition image onto the physical disk partition, it appears that the disklabel is damaged. I have a saved ASCII copy of the disklabel as NetBSD saw it originally, and I trust it because:
a) the offset and size values step correctly with no math errors;
b) the SWXCR drive type reported by NetBSD corresponds with the Digital UNIX /etc/disktab file's 're' device and SWXCR disk type, which is described as a DEC RAID Controller with dynamic geometry.
c) the size of the c partition from offset zero is the same as the total sectors, so the c partition size correctly fills the entire logical disk.
I will comment idly that I needed to switch to 'set console graphics' mode to boot the installation CD, and also plug in a keyboard and mouse, but I did find the shell prompt. I rather prefer the serial console because it's so much easier to use 'script' to keep an audit trail of what I did and what response I got, and to paste console output from the serial 'cu' utility than to re-type everything from the graphics console. But I couldn't seem to get the CD to boot up in serial console mode. Now that I see it is an X-based install, that makes sense, I guess. But when booting with my laptop acting as a serial console (and no keyboard or mouse, I should confess), I never did get any console nor VGA output that hinted that anything was going on beyond the "jumping to bootstrap code" message. After I switched to console graphics mode, I started getting results.
Once at a shell, I did:
# cd /dev
# ./MAKEDEV re0
# disklabel -r re0
and saw the damaged label, which reinforced my suspicion that the disklabel really was gone. The type, disk, and most all the geometry values were not correct, compared to the SWXCR label that NetBSD saw several days ago.
I tried writing a new label to the disk:
# disklabel -wr -t advfs re0
That command gave me:
disklabel: ioctl DIOCSDINFO: Open partition would move or shrink
Use alternate partition
I took a feeble stab at editing the new label to my liking:
# TERM=vt100;export TERM
# EDITOR=vi;export EDITOR
# disklabel -e re0
I changed only the size and offset values (deleting the partitions I didn't want), and left all the header disk, type, and geometry values at their (incorrect) defaults. I changed the 'a' partition fstype to 'unused' and left the other fstype values alone, since they already said 'unused'.
Since I didn't change the incorrect geometry values (which were generally smaller than they should be), I'm not surprised that when I tried to write the edited disklabel, I was told in essence that the partitions overflowed the limits of the disk.
For kicks, here are the "then-and-now" values of the disklabel header fields:
type: ccd now says SCSI
disk: SWXCR now says RZ28
sectors/track was 32, now 99
tracks/cyl was 128, now 16
sectors/cyl was 4096, now 1584
cyls was 8683, now 2595
total sectors was 35565568, now sectors/unit is 4110480
rpm was 3600, now 5376
interleave is 1 on both labels
trackskew, cylinderskew, headswitch, trk-to-trk seek, drivedata are
all 0 on both labels
As you can see, the geometry on the RZ28 label is much smaller. Not surprisingly, when I edit and try to write the label to disk, I am told that the partitions exceed the size of the disk.
I've rarely read /etc/disktab, but reading Tru64's disklabel man page gave me an interest. The type SWXCR is indeed defined in that file, in conjunction with the re device name, described as a DEC RAID Controller (multi-spindle), and references dynamic_geometry in the disktab 'ty' field.
Attempting to create a label with:
disklabel -wr -t advfs re0 SWXCR
yields the same error DIOCSDINFO error message.
Here's something I just found:
'print a default label'
disklabel -p re0
displays a disklabel with largely correct geometry: type SWXCR, disk SWXCR, flags: dynamic_geometry, 512 bytes/sec, 32 sec/trk (check), 128 trk/cyl (check), 4096 sec/cyl (check), 8683 cyls (check), 35565568 total sectors (check). 3600 rpm, interleave 1, all else 0. The partitions are wrong, but I can edit those.
Shall I write the 'disklabel -p re0' to an ASCII file, edit the ASCII file to have the right partitions, and then tell disklabel to write the label to disk based on that?
Would that be:
disklabel -p re0 > /tmp/re0.label
vi /tmp/re0.label
disklabel -Rr -t advfs re0 /tmp/re0.label
??
Thank you!
Jim
