gpart and bsdlabel

[Polytropon]

On Fri, 11 Jul 2014 15:02:45 -0600 (MDT), Warren Block wrote:
> On Fri, 11 Jul 2014, Michael W. Lucas wrote:
> [...]
> > Is there a way to specify which partition letter you want to create,
> > or start with, or something?
> 
> Interesting question.  I always figured the letters were dynamic.  If 
> they are static, maybe -l could be used to assign them to BSD 
> partitions.

The letters can be from 'a' to 'h' and are assigned in the
way the label actually contains them, if I remember correctly,
with the exception that:

	'a' has to be the 1st partition if you want to boot
	    from it
	'b' is reserved for swap
	'c' is "the whole thing" (whole slice, whole disk)

Here's an actual example:

% bsdlabel ad4s1
# /dev/ad4s1:
8 partitions:
#          size     offset    fstype   [fsize bsize bps/cpg]
  a:    2097152          0    4.2BSD        0     0     0
  b:    4194304    2097152      swap                    
  c:  625142385          0    unused        0     0     # "raw" part, don't edit
  d:    2097152    6291456    4.2BSD        0     0     0
  e:    2097152    8388608    4.2BSD        0     0     0
  f:  104857600   10485760    4.2BSD        0     0     0
  g:   10485760  115343360    4.2BSD        0     0     0
  h:  499313265  125829120    4.2BSD        0     0     0

It would be interesting to see if the label is edited in a
"strange" manner. After initialization, only 'c' is present.
Now one could add a 'f' partition at the first position, and
maybe 'd' later on and declare it as swap...



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