FreeBSD 9.3 new install problems ....

Polytropon freebsd at edvax.de
Sat Aug 2 21:43:46 UTC 2014


On Sat, 02 Aug 2014 16:08:13 -0500, William A. Mahaffey III wrote:
> P.S. sorry for me klutzy nomenclature, I am calling /dev/ada0p3 a 
> partition, when as you correctly observe it is a device .... my bad, & 
> maybe the source of confusion in my posts :-/ ....

You're _not_ doing it wrong. :-)

The _file_ /dev/ada0p3 represents a GPT partition (the 3rd GPT
partition of the 1st SATA disk). It's valid to refer to /dev/ada0p3
as a partition. A partition carries a file system.

For comparison: /dev/ad0s1 would be called a slice, which is
synonymous for a "DOS primary partition", or MBR partition.
The _real_ partition carrying a file system would be /dev/ad0s1a,
for example (the 1st partition of the 1st slice of the 1st ATA
disk). If a dedicated approach would have been taken, i. e., the
slicing part omitted, /dev/ad0a would be a partition (the 1st
partition of the 1st ATA disk). While a slice can carry many
partitions (file systems) - 'a' = bootable, 'b' = swap, 'c' = 
the whole thing, 'd', 'e' and so on -, a GPT partition only
carries one partition (a file system) - 'c', and this letter
is simply omitted.

ad0, da0, ada0 -> disk
ad0p1 -> GPT partition
ad0s1 -> MBR partition = slice (carries partitions)
ad0s1a, ad0s1d -> partition
ad0a -> bootable partition (dedicated)
ad0 -> partition (dedicated, "data partition"), it's ad0c

Note that all non-GPT partitioning has little meaning today, but
it's worth knowing the difference and history in order to use the
correct terminology with confidence. :-)



-- 
Polytropon
Magdeburg, Germany
Happy FreeBSD user since 4.0
Andra moi ennepe, Mousa, ...


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