gpart add -a 4096 vs 4k

[Irjohn Junus]

Olivier,

Thanks for your quick reply and you're right, '4k' = '8'!

# gpart add -t freebsd-zfs -l hdd0 -a 8 da0
da0p1 added
# gpart show da0
=>        34  3907029101  da0  GPT  (1.8T)
          34           6       - free -  (3.0k)
          40  3907029088    1  freebsd-zfs  (1.8T)
  3907029128           7       - free -  (3.5k)



Thanks,
Ronjns




On Wed, Jun 13, 2012 at 6:18 PM, Olivier Smedts <olivier at gid0.org> wrote:

> Hello,
>
> 2012/6/13 Irjohn Junus <i.junus at gmail.com>:
> > Hello,
> >
> > Relatively new to FreeBSD and learning, I'm trying to partition my HDD
> and
> > align it to 4k sector.
> >
> > I do apologize if this has been answered before, I have Googled and read
> > gpart(8) man page to no joy. Can anyone please advice why gpart add '-a
> > 4096' doesn't yield the same result with '-a 4k'? Many thanks and
> captures
> > are below.
> >
> > Regards,
> > Ronjns
> >
> >
> >
> > #gpart add -t freebsd-zfs -l hdd0 *-a 4096* da0
> > da0p1 added
> > # gpart show da0
> > =>        34  3907029101  da0  GPT  (1.8T)
> >          34        4062       - free -  (2M)
> >        *4096  3907022848*    1  freebsd-zfs  (1.8T)
> >  3907026944        2191       - free -  (1.1M)
> >
> >
> >
> > # gpart add -t freebsd-zfs -l hdd0 *-a 4k* da0
> > da0p1 added
> > # gpart show da0
> > =>        34  3907029101  da0  GPT  (1.8T)
> >          34           6       - free -  (3.0k)
> >          *40  3907029088*    1  freebsd-zfs  (1.8T)
> >  3907029128           7       - free -  (3.5k)
>
> We're talking of sectors here, se "4096" does not mean 4 KB but
> 4096*512=2MB.
>
> I think you should use "-a 8", because 4k sectors = 8*512B sectors.
>
> --
> Olivier Smedts                                                 _
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