gmirror

[tradigan at newrevolutions.net]

Quick question, I am configuring gmirror to mirror certain slices on my
hard drives.. I want to mirror /dev/ad0s1 (700M) to another drive.. I am
fine with configuring gmirror and getting it running but I am unsure of
how I create the BSD slices with bsdlabel -e..

When I do a bsdlabel -e /dev/ad0s1 I get:

# /dev/ad0s1:
8 partitions:
#        size   offset    fstype   [fsize bsize bps/cpg]
  a:   409600        0    4.2BSD     2048 16384 25608
  c:  1429722        0    unused        0     0         # "raw" part,
don't edit
  d:  1020122   409600    4.2BSD     2048 16384 63760

When I initially create the mirror on the backup disk, I run a bsdlabel -e
/dev/mirror/gm0s1 and this is what it shows:

# /dev/mirror/gm0s1:
8 partitions:
#        size   offset    fstype   [fsize bsize bps/cpg]
  a:  1429705       16    unused        0     0
  c:  1429721        0    unused        0     0         # "raw" part,
don't edit

My initial instinct was to mirror the bsdlabel output from ad0s1 but with
just the 16 offset for the 'a' slice coming out with:

# /dev/mirror/gm0s1:
8 partitions:
#        size   offset    fstype   [fsize bsize bps/cpg]
  a:  409584        16    4.2BSD     2048 16384 25608
  c:  1429721        0    unused        0     0         # "raw" part,
don't edit
  d:  1020122   409584    4.2BSD     2048 16384 63760

Is my assumption correct?  Or am I missing something here?