SUMMARY: ufsdump aborts "cannot read sector..." then fsck fails

From: Philip Hurvitz (phurvitz@u.washington.edu)
Date: Mon May 04 1998 - 16:58:27 CDT


Thanks to the following:

"Marc S. Gibian" <gibian@stars1.hanscom.af.mil>
Sanjaya Srivastava <Sanjaya.Srivastava@Eng.Sun.COM>
"Boland, John" <bolandj@bsci.com>
DBell@mobile.bam.com
"Michael J. Connolly" <mjconnly@newton41.ckcorp.com>
Ronald Loftin <reloftin@mailbox.syr.edu>
Casper Dik <casper@holland.Sun.COM>

In general, it appears that there were some fairly serious disk errors.
Luckily, the student who was most concerned said she could live with last
month's data. Therefore, I tried all suggestions (which either failed or
did not help) and did a ufsrestore (brute force method). I'll keep my eye
on this disk.

The responses included:
1) attempt a read-only mount
        mount -o ro /dev/dsk/c0t1d0s2 /d1
        mount -o ro /dev/rdsk/c0t1d0s2 /d1
        (couldn't mount)

2) attempt format/analyze
        (failed: "disk not formatted" error)

3) fsck with a different superblock
        fsck -ob=32 /dev/rdsk/c0t1d0s2
        (failed: other sectors were also unreadable.)

4) /usr/sbin/fsdb
        (I didn't try this; I was already restoring when I got the mail)

5) attempt to copy data from the disk to another identical disk (using dd)
        (no other identical disk around here)

6) check the log file for SCSI errors
        the log file is FULL of SCSI errors.
        I also got these messages after the restore started.
        A possible culprit....

Thanks once again!!

-P.

***************************************************************************
 Phil Hurvitz | GIS Specialist | College of Forest Resources | 355 Bloedel
Box 352100 | University of Washington, Seattle, Washington 98195-2100, USA
 tel: 206.685.8179 | FAX: 206.685.3091 | e-mail: phurvitz@u.washington.edu
             WWW: http://weber.u.washington.edu/~phurvitz/
***************************************************************************

§Date: Mon, 4 May 1998 09:57:59 -0700 (PDT)
§From: Philip Hurvitz <phurvitz@u.washington.edu>
§To: "sun-managers@ra.mcs.anl.gov" <sun-managers@ra.mcs.anl.gov>
§Subject: ufsdump aborts "cannot read sector..." then fsck fails
§MIME-Version: 1.0
§
§Platform: Sun Ultra 1
§OS: Solaris 2.5.1
§
§I was performing a monthly backup (ufsdump) and got this error:
§
§DUMP: 86.22% done, finished in 0:09
§DUMP: Warning - cannot read sector 7284672 of `/dev/rdsk/c0t1d0s2'
§
§I then attempted an fsck, but got this error:
§
§fsck -F ufs /dev/rdsk/c0t1d0s2
§** /dev/rdsk/c0t1d0s2
§
§CANNOT READ: BLK 16
§CONTINUE? y
§
§THE FOLLOWING SECTORS COULD NOT BE READ: 16 17 18 19 20 21 22 23 24 25 26
§27 28 29 30 31
§
§I cannot mount the disk. I cannot fsck the disk. I'd like to be able to
§access data that are on the disk now before attempting to format and
§newfs (a student's data are on the disk - a lot of important stuff that is
§more recent than last month's backup).
§
§I'll be grateful for any help on this.



This archive was generated by hypermail 2.1.2 : Fri Sep 28 2001 - 23:12:39 CDT