can I make a reset-at-will box?

[Les Mikesell]

On Sun, 2005-10-09 at 07:37, Tim wrote:

> > Use a journalising file system such as ext3?
> 
> I do, but during testing (where I've hit the reset button and pulled out
> the power leads), I've seen warnings about not being shutdown properly
> and fsck should be done on the drive.  I don't know how much I can
> ignore such warnings, and just carry on hoping for the best.

Some drives buffer data internally so even the best attempts by
the OS to sync at journal points might fail to record what it
expects.  That's the point of the warning.  Normally replaying
the journal will recover the filesystem to a consistent state
although of course you still lose any unflushed data from
working applications.

> It'd be better if there was no need to "recover", that the drive was
> only being written to if you were actually saving data to it.

Files need to be closed to be sure the applications have
flushed all outstanding data.  The system writes data to
various logs all the time, so there will always be open
files in a running system.  The OS marks filesystems as
'clean' on the way down if all the files are closed and
it is unmounted properly.   You can help the situation by
separating the filesystems - some can even be mounted
read-only.

-- 
  Les Mikesell
    lesmikesell at gmail.com