Subject: Re: ccd, disklabel
To: None <email@example.com>
From: Jens A Nilsson <firstname.lastname@example.org>
Date: 11/02/1998 21:08:36
Tom T. Thai <email@example.com>,wrote on Nov 02, 1998 at 13:09 -0600:
> On Mon, 2 Nov 1998, Jens A Nilsson wrote:
> > The problem is that you need an offset for the partitions you ccd.
> > Look at ccd(4), it's described in the beginning of the manpage.
> man ccd:
> Note that the `raw' partitions of the disks should not be combined.
> Each component partition should be offset at least one cylinder from
> the beginning of the component disk. This avoids potential conflicts
> between the component disk's disklabel and the ccd's disklabel. The
> kernel will only allow component partitions of type FS_BSDFFS.
> given that all my disks are laid out the same per disklabel below for each
> # size offset fstype [fsize bsize cpg]
> a: 224700 0 4.2BSD 1024 8192 16 # (Cyl. 0-99)
> b: 224700 224700 swap # (Cyl. 100-199)
> c: 8340864 0 unused 0 0 # (Cyl. 0-3711)
> d: 8340864 0 unused 0 0 # (Cyl. 0-3711)
> e: 7891464 449400 4.2BSD 1024 8192 16 # (Cyl. 200-3711)
> so if I want to ccd each partition of each disk sdXa into ccd1, then I
> have to offset partition a from the original disklabel? i.e. partition a
> above (for each sdx) should be:
> a: 224700 1 4.2BSD 1024 8192 16 # (Cyl. 0-99)
> --- <-- changed from 0 to 1
Change that to what's written after "sectors/cylinder:"
> what about partition e for each disk? should that be offset by one too?
> i have ccd0 using all the partitions sdXe right now with out that offset.
No that's not necessary since there is no risk for conflict there.
> oh a side note, where is the disklabel for a ccd really written?
Since you got the disklabel from sd0 I suppose that it's put at
the begining of the first partition you ccd.