How to label a GELI device

[J. Porter Clark]

On Tue, Jan 25, 2011 at 07:28:25PM +0100, Rolf Nielsen wrote:
> X-Spam-Level: 
> 
> 2011-01-25 19:13, J. Porter Clark skrev:
> > On Tue, Jan 25, 2011 at 03:29:37PM +0100, Rolf Nielsen wrote:
> >>
> >> Correct me if I'm wrong anyone.
> >> You need to first label da0s1d
> >>
> >> e.g. like so
> >>
> >> glabel label data da0s1d
> >>
> >> then geli init the labeled device
> >>
> >> e.g. like so
> >>
> >> geli init -l 256 -s 4096 label/data
> >
> > Unfortunately, this step overwrites the label.
> 
> It does not. I just tested it with a file backed md device, and 
> hexdumped it after each step (creating the file, mdconfig it, label the 
> md device and encrypting it).
> After the first two steps, I got just zeros, after labeling it, I got 
> the last sector containing the label, and after encrypting it, I got the 
> second last sector (i.e. the last sector of the labeled device) 
> containing the eli data and the last secor still containing the label.
> 
> If it does overwrite the label, you most likely specified the da0s1d to 
> the geli init command. You need to specify label/data (replace "data" 
> with the name you choose).

Ah!  That is, in fact, exactly what I did.  I didn't realize
that the glabeled device was actually shrunk by 1 sector.

Thanks!

-- 
J. Porter Clark      <jpc at porterclark.com>