After crash, / comes up mounted read-only, but in multiuser; mfs /tmp?

[David Xu]

Robert Watson wrote:

>
> While testing the new DRM update (went badly :-), I crashed my system 
> and had to power cycle it.  When it came back up, not surprisingly, 
> the file systems weren't clean.  When I reached a login prompt, I 
> logged in to modify /etc/rc.conf, and to my surprise, was told that 
> /etc/rc.conf wasn't writable.  Turns out it was because / was mounted 
> read-only:
>
> ad0: 57231MB <HTS541060G9SA00 MB3IC60H> at ata0-master SATA150
> acd0: CDRW <HL-DT-STCD-RW/DVD DRIVE GCC-4246N/0X05> at ata1-master UDMA33
> Trying to mount root from ufs:/dev/ad0s3a
> WARNING: / was not properly dismounted
> Loading configuration files.
> kernel dumps on /dev/ad0s3b
> Entropy harvesting: interrupts ethernet point_to_point kickstart.
> swapon: adding /dev/ad0s3b as swap device
> Starting file system checks:
> /dev/ad0s3a: INCORRECT BLOCK COUNT I=16528 (4 should be 0) (CORRECTED)
> /dev/ad0s3a: UNREF FILE I=16528  OWNER=root MODE=100444
> /dev/ad0s3a: SIZE=0 MTIME=Dec  2 10:33 2005  (CLEARED)
> /dev/ad0s3a: FREE BLK COUNT(S) WRONG IN SUPERBLK (SALVAGED)
> /dev/ad0s3a: SUMMARY INFORMATION BAD (SALVAGED)
> /dev/ad0s3a: BLK(S) MISSING IN BIT MAPS (SALVAGED)
> /dev/ad0s3a: 2378 files, 78670 used, 175145 free (441 frags, 21838 
> blocks, 0.2%
> fragmentation)
> /dev/ad0s3e: DEFER FOR BACKGROUND CHECKING
> /dev/ad0s3d: DEFER FOR BACKGROUND CHECKING
> WARNING: /usr was not properly dismounted
> WARNING: /var was not properly dismounted
> /var: mount pending error: blocks 4 files 1
> Setting hostname: sesame.cam.watson.org.
> bge0: link state changed to DOWN
> bge0: no link ....bge0: link state changed to UP
>
> ...
>
> /dev/ad0s3a on / (ufs, local, read-only)
> devfs on /dev (devfs, local)
> /dev/ad0s3e on /usr (ufs, local, soft-updates)
> /dev/ad0s3d on /var (ufs, local, soft-updates)
> /dev/md0 on /tmp (ufs, local)
>
> The rc scripts helpfully mounted an MFS /tmp for me, which while 
> friendly, succeeded in masking the problem and allowing the system to 
> come up in a rather undesirable state (from my perspective).  So it 
> sounds like maybe / wasn't remounted properly, and then the scripts 
> were too helpful thinking it was a diskless system.
>
> Robert N M Watson
>
I have seen this for some days,  one machine I even have to reinstall
the system because mount -u / does not work. :-(

David Xu