Path: utzoo!mnetor!uunet!husc6!bloom-beacon!mit-eddie!bbn!rochester!ur-tut!ur-valhalla!socrates.ee.rochester.edu!deke
From: deke@socrates.ee.rochester.edu (Deke Kassabian)
Newsgroups: comp.unix.wizards
Subject: Re: 4.3 BSD VAX 11/750 does not seem to sync its disks.
Message-ID: <1237@valhalla.ee.rochester.edu>
Date: 5 Apr 88 14:35:40 GMT
References: <271@usfvax1.UUCP> <10900@mimsy.UUCP> <1967@quacky.mips.COM>
Sender: usenet@valhalla.ee.rochester.edu
Reply-To: deke@socrates.ee.rochester.edu (Deke Kassabian)
Organization: UR Dept. of Electrical Engg, Rochester NY 14627
Lines: 33


In article <1967@quacky.mips.COM> dce@quacky.UUCP (David Elliott) writes:
>In article <10900@mimsy.UUCP> chris@mimsy.UUCP (Chris Torek) writes:
>>In article <271@usfvax1.UUCP> brankley@usfvax1.UUCP (Bob Brankley) writes:
>>>I have been having a pretty wild problem on my VAX 11/750 running 4.3
>>>BSD ....  I originally found the problem when my nightly "fsck" of the
>>>file system detected multiple UNREFerenced files in the partition
>>>containing my user files(/dev/ra0g).
>>
>>You cannot run fsck on an active file system.  Among other things,
>>it should not be necessary.  Stop doing it.
>
>Sadly, 4.3BSD comes this way.  /usr/adm/daily.sh (an otherwise great
>way of doing periodic chores, superior to crontab, anyway) runs
>/etc/fsck with the -n option.  Sure, the sync command is executed
>first, but that doesn't guarantee anything at all.

Sync may not guarentee anything, but the -n option does.  What's the problem
here?  Using the -n option does not open the file system for writing. How
wrong can you go?  I find using fsck this way extremely useful, and the
worst thats happened so far is a couple of reports of file system problems
that were clearly the result of an "active" system.  If they "go away" the
next time fsck is run (at 4am) then I don't worry.  If they hang around for
a few days, its probably a legitimate problem and I'll deal with it then.
And there have been a few, and I've caught them quickly this way.

Overall this is far better than waiting for the next time a system crashes
or otherwise reboots to run fsck.  Is it really "smarter" to bring a system
down to single user every X days to check file system consistancy??
 
 \\\  Deke Kassabian, URochester Department of Electrical Engineering  \\\
  \\\ deke@ee.rochester.edu                  "I never metacharacter     \\\
   \\\   or ...!rochester!ur-valhalla!deke     I didn't like......"      \\\