Problem:
Have DEC Alpha 3000/600 _at_ v3.2c with all ADVfs filesystems.
A reboot failed so booted single user from install CD ROM to get at root fs.
Could not read root partition; this is what I had tried:
cd /dev; ./MAKEDEV rz3; mkdir -p /etc/fdmns/root_domain;
ln -s /dev/rz3a /etc/fdmns/root_domain/rz3a;
Now the mount resulted int:
# mount -t advfs root_domain_at_root /mnt
root_domain#root on /mnt: Device does not contain a valid ADVFS file system
Two questions:
A. So was the disklabel info mangeled? disklabel -r showed proper partitioning
with fstypes ADVfs for a and g as should be. Can I rewrite the disklabel
without hosing the a (root) and g partition data?
Answer: yes, you should be able to do that. 2 Methods:
1.from Kurt Carlson: remove existing label & write anew and edit to taste:
disklabel -z rz3 remove existing label
disklabel -t advfs rz3 rz28l write new
disklabel -e rz3 edit to restore custom partitioning (if any)
2. from Knut Helleboe: don't explicitly remove existing label
disklabel -t advfs -e rz3
B. If I suspect the ADVfs filesystem is mangled, can I fix it similar to fsck
on a ufs filesystem?
Answer: Usually not:
1. from Peter Flack: 2 utilities, but they require the ADVfs to be mounted -
msfsck and vchkdir located in /usr/field
-To use msfsck, cd to the mount point (where the .tags file is) and use]
/usr/field/msfsck domainname setname for each fileset
-To use vchkdir use vchkdir mountpointdir; see man page for options
Many thanks to
Kurt Carlson <SXKAC_at_orca.alaska.edu>
Peter Flack flack_at_rtp4me.ENET.dec.com
Knut Hellebo <Knut.Hellebo_at_nho.hydro.com>
Full responses follow:
=============================================================================
From: Kurt Carlson <SXKAC_at_orca.alaska.edu>
> For ufs, fsck will go out and fix the boot blocks and filesystem. What is
> the comparable for advfs; or:
I think you're out of luck on the above.
> * Can I write a new disklabel to that disk, making sure to use the same
> partition table, without destroying the former data and allowing mount of
> the original advfs root and usr file systems? --- I suspect that I might
> because the DU install process (from 2.0 to 3.2c) gave me an option to use
> existing disklabel partitions found on disk.
Yes, you can. disklabel -z, followed by disklabel -t advfs, followed
by disklabel -e if you didn't earlier use standard partitions. I had to
use this on a disk which was cloned to become a new boot disk which had
not been initially labeled as -t advfs (so it wouldn't boot)... so i
know it works.... the label is a fixed area.
However, if something wiped out your label there is a great deal of
risk that it wiped out something else on the disk, too... either
data or advfs meta-data. Before trying to use the disk try to
do a showfsets, that will tell you if the meta-data is still intact.
good luck, kurt carlson, u of alaska
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From: flack_at_rtp4me.ENET.dec.com
There are two utilities for looking at AdvFS filesystems, but I think they
both require the AdvFS filesystem to be mounted....
They are located in /usr/field and are called msfsck and vchkdir. I am on the
road and my laptop was being repaired (and is now waiting for me at home) - it
contains my notes on these utilities... To use msfsck, cd to the mount point
(where the .tags file is) and use /usr/field/msfsck domainname setname for each
fileset. To use vchkdir use vchkdir mountpointdir - problem is I can't
remember what the various options are (and I don't have my notes....).
------------
From: Knut Helleboe <Knut.Hellebo_at_nho.hydro.com>
It should be safe to do a
disklabel -t advfs -e rz3
and write out the new label without altering the partitions.
-----------------------------------------------------------------------
Neil R. Smith, Research Assoc./Comp.Sys.Mngr. neils_at_csrp.tamu.edu
Climate System Research Program 409/862-4342
Dept. of Meteorology, Texas A&M Univ., USA 409/862-4132 FAX
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Received on Wed Mar 06 1996 - 01:19:51 NZDT