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Re: LABEL's



On Fri, 31 Aug 2007, Timothy Murphy wrote:

> Jacques B. wrote:
>
> > On 8/30/07, Timothy Murphy <tim birdsnest maths tcd ie> wrote:
> >> Jacques B. wrote:
> >>
> >> > Your first part is correct.  You can dd a smaller partition onto an
> >> > equal or larger one.
> >>
> >> Are you sure you can dd onto (or rather into) a larger partition?
> >> I tried that some years ago, and it led to confusion, IIRC.
> >
> > Yes you can.  You end up with slack space at the end of the partition.
> >  In other words if you dd a 10 gig drive onto a 30 gig drive, you will
> > have what appears to be a 10 gig drive.  The remaining 20 gigs will be
> > unused.
>
> I understand the theory.
> But in my (very limited) experience, the conflicting information
> on the system may cause confusion.
> What for example does fdisk say?
> The MBR presumably will think you have a 30 gig drive.

undoubtedly, it will.  beyond the (up to) 446 bytes of actual code in
the MBR, there's room for a 64-byte partition table, with 4 16-byte
entries.  what those partitions contain is of no interest to the
actual partition table, so if you create a "short" filesystem in a
partition, the MBR will have no idea about that.

rday

p.s.  what the last two bytes of the MBR contain is left as an
exercise for the reader.  :-)
-- 
========================================================================
Robert P. J. Day
Linux Consulting, Training and Annoying Kernel Pedantry
Waterloo, Ontario, CANADA

http://crashcourse.ca
========================================================================


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