fsck unable to read disk sectors

[Matt Thyer]

It wouldn't be the BSD way to try to stop the user shooting themselves
in the foot.
And I agree too as it wouldn't be right for glabel to try to keep
track of all possible uses for a volume and know whether each is
present.
That would be a typical Linux type solution.

However, would it be too much for glabel to just know about UFS and
tell the user to use tunefs instead if there appears to be a UFS
filesystem present ?

On 17 May 2010 23:32, Bernd Walter <ticso at cicely7.cicely.de> wrote:
> On Mon, May 17, 2010 at 10:54:17PM +0930, Matt Thyer wrote:
>> On 12 May 2010 11:16, Bernd Walter <ticso at cicely7.cicely.de> wrote:
>> >
>> > On Tue, May 11, 2010 at 10:15:13PM +0200, Alexander Best wrote:
>> > > i've posted a log here which is pretty self explanatory:
>> > >
>> > > http://pastebin.com/tn3NiDDW
>> > >
>>
>> [snip]
>>
>> >
>> > One of the typical problems users have is that they forget that
>> > adding a label takes one sector, so the labeled device is smaller.
>> > This is no problem if you create the filesystem on the labeled
>> > drive, but often enough people add the label after creating the
>> > filesystem.
>>
>> FreeBSD's utilities should be able to detect this situation and either
>> correct the filesystem size or refuse to apply the label.
>
> How can this work?
> glabel doesn't know anything about volume contents - it just writes a
> label-sector and offers the remaning storage as a new volume.
> Result: Refusing is impossible.
> Changing UFS filesystem size isn't an easy task and the last sector is
> already lost when filesystem comes into game.
> Result: Too late.
> I think the only reasonable thing to be done is that fsck can speak
> up by checking the volume size with the filesystems size _after_ glabel
> has overwritten the last sector.
>
> --
> B.Walter <bernd at bwct.de> http://www.bwct.de
> Modbus/TCP Ethernet I/O Baugruppen, ARM basierte FreeBSD Rechner uvm.
>