[comp.unix.ultrix] Fsck 2.2 vs 3.0

rick@ut-emx.UUCP (Rick Watson) (05/12/89)

Why doesn't fsck think my disks were "unmounted cleanly" when I 
switch between Ultrix 2.2 and 3.0?  I'm shutting down with 
"/etc/shutdown -h now".  This doesn't occur if I reboot the system
that was running.

Is there a workaround?  Is there something dangerous happening that
I should know about?

Rick Watson
University of Texas Computation Center
 arpa:   watson@utadnx.cc.utexas.edu (128.83.1.26)
 uucp:   ...cs.utexas.edu!ut-emx!rick
 bitnet: watson@utadnx
 span:   utspan::watson (UTSPAN is 25.128)
 phone:  512/471-8220 512/471-3241

thomas@mipsbx.dec.com (Matt Thomas) (05/12/89)

> Why doesn't fsck think my disks were "unmounted cleanly" when I 
> switch between Ultrix 2.2 and 3.0?  I'm shutting down with 
> "/etc/shutdown -h now".  This doesn't occur if I reboot the system
> that was running.

In each release of Ultrix, the kernel and fsck share a magic number
that indicated whether a file system has been unmounted cleanly.  This
magic number is different for each release of Ultrix.  Actually this
number changes fairly often (like each baselevel) during the development
of a release.

The reason for the changing of the number is that each baselevel makes
certain assumptions about the consistency of filesystem.  The only way
to insure consistency to make sure fsck and the kernel are built at the
time and they are at the same revision level.

-- 
Matt Thomas                     Internet:   thomas@decwrl.dec.com
DECnet-Ultrix Development       UUCP:       ...!decwrl!thomas
Digital Equipment Corporation   Disclaimer: This message reflects my own
Littleton, MA                               warped views, etc.

grr@cbmvax.UUCP (George Robbins) (05/12/89)

In article <12982@ut-emx.UUCP> rick@ut-emx.UUCP (Rick Watson) writes:
> Why doesn't fsck think my disks were "unmounted cleanly" when I 
> switch between Ultrix 2.2 and 3.0?  I'm shutting down with 
> "/etc/shutdown -h now".  This doesn't occur if I reboot the system
> that was running.

The story present a while back was that the "dirty" flag was changed
for compatibility with the 4.3BSD "dirty" flag, to preserve filesystem
interchangability.  I don't know if this is precisely true, however
the release notes do warn about the situation. 

> Is there a workaround?  Is there something dangerous happening that
> I should know about?

Nothing dangerous is happening.  If you are confident that your filesystems
are not corrupt then go ahead and do a "mount -o force ..." or let the fsck
run each time.  Do let it fsck once in a while for luck and job security.

Once you stablize on 3.0, the problem will go away.  

-- 
George Robbins - now working for,	uucp: {uunet|pyramid|rutgers}!cbmvax!grr
but no way officially representing	arpa: cbmvax!grr@uunet.uu.net
Commodore, Engineering Department	fone: 215-431-9255 (only by moonlite)