[Pkg-sysvinit-devel] Bug#568251: Bug#568251: Please support fsck on shutdown

[Henrique de Moraes Holschuh]

On Tue, 09 Feb 2010, Goswin von Brederlow wrote:
> Henrique de Moraes Holschuh <hmh at debian.org> writes:
> > Sort of.  Boot either has to check any dirty filesystems, or halt and go
> > into a sulogin-or-shutdown loop.   You must NOT skip a dirty filesystem
> > check at boot and continue with system startup, EVER.  We can't even offer
> > that as a choice, it is known to cause worse data loss if the fs is corrupt.
> 
> I think you mean filesystem with errors instead of dirty. A dirty

Yes.  But how can you know that a dirty fs is not corrupt without a fsck?

> ext3/4, xfs or reiserfs just needs a journal replay. Didn't think of the

Depends on the underlying storage.  A power loss event and use of write
caches in the wrong way can corrupt ext3/4/xfs.  Also, corruption is very
likely if such an event happens in many types of flash-based storage as it
will hork an entire flash erase block.

> error case though. Filesystems might have gotten the error bit set
> during operations.

That's another possibility, yes.

> But I'm not sure that changes anything in the suggested behaviour. On
> shutdown it would do the same as during boot, except prompt for the root
> password. It always continous on shutdown no matter how bad the check
> was.

Well, whatever trick we will use to avoid periodic fsck on *boot* must NOT
cause a dirty filesystem check to be skipped.  That's all I am saying.

And, AFAIK, the only way to do that right now is to disable the periodic
triggers in the filesystems, and implement the periodic trigger entirely in
the initscripts, so that we can ignore it on boot, but honour it on
shutdown.

-- 
  "One disk to rule them all, One disk to find them. One disk to bring
  them all and in the darkness grind them. In the Land of Redmond
  where the shadows lie." -- The Silicon Valley Tarot
  Henrique Holschuh