two basic approaches to serving this need were discussed.
here's how i understood and would express them:
1. specify, as one of the four mbr partition slots, any arbitrary
location on the disk.
2. specify, as one of the four mbr partition slots, the location
of an existing logical partition.
option 1 is completely general. the user may or may not break
the "rule" about non-overlapping partitions depending on what
data the user enters. what happens when that slot in the mbr
is used for some other partition? if the usurped partition was
a logical partition, the effect is the same as with option 2,
described below. if the partition was not a logical partition,
then the partition is no longer visible, which is inconvenient.
far worse, it is technically unallocated, so other software
will happily overwrite it. this is extremely dangerous, in the
sense that partitioning software will think it's ok to scribble
all over the usurped partition. it is completely down to the
user to avoid such potentially "catastrophic" mistakes.
option 2 is much less general. it automatically breaks the
"rule" about non-overlapping partitions. what happens when
that slot in the mbr is used for some other partition? the
usurped partition is visible to all software as a normal
logical partition. in this sense, option 2 is convenient
and safe.
having tried both, and having seen what existing software and
both good and sloppy user habits do in both cases, i personally
much (understatement) prefer option 2.
--
ralph mellor
