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Date: Mon, 13 May 1996 01:47:44 -0700 (PDT)
Message-Id: <199605130847.BAA04203@silvia.HIP.Berkeley.EDU>
To: current@freebsd.org, stable@freebsd.org
CC: nisha@cs.berkeley.edu
Subject: Heads-up: ccd offset 16 change committed
From: asami@cs.berkeley.edu (Satoshi Asami)
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I just committed changes to ccd.c to not use the first 16 blocks in
each of the underlying partitions.  What this means is that you can
stop worrying about starting the partitions for ccd too close to the
beginning of the slice.

Anything that works for FFS will also work for ccd, including the "c"
partition (which, I think, is what most people would want to use for
ccd anyway).

The downside of this is that if you already have a ccd set up on your
machine, it will stop working when you recompile the kernel from the
latest sources.  To avoid this, you should either (1) change the
disklabel to move the partitions 16 sectors towards the beginning of
the disk, or (2) change the definition of CCD_OFFSET to 0 in
sys/dev/ccd/ccd.c.  Or just back up, recompile, and restore.

I believe this would be the last major change in the ccd layout in the
forseeable future.  (Well there still might be, but at least I don't
anticipate anything anytime soon, that's why it's called "forseeable". :> )

Happy concatenating!

Satoshi