Re: Setting up raid correctly

[Manuel Bouyer <bouyer%antioche.eu.org@localhost>]

On Sun, Feb 24, 2013 at 05:00:07PM +0000, Philip Mueller wrote:
> If I partition wd3 single, then I can't setup a raid1 on it.
> Because:
> spectre# dd if=/dev/zero of=/dev/wd3d
> ^C8457+0 records in
> 8456+0 records out
> 4329472 bytes transferred in 3.467 secs (1248766 bytes/sec)
> spectre#gpt show wd3
>        start        size  index  contents
>            0  3907029168
> spectre#gpt create wd3
> spectre# gpt add -t ffs wd3

You didn't understand what I wrote. You have to create the partition on wd3
*after* setting up the raid1 and creating the filesystem on it.
The start of the partition on wd3 has to match the location of the ffs
on raid1, shifted by the raid1 metadata, which, I think, is 128 sectors.
Also, you may have to create a raid-type partition on wd3 so that
the partition table on wd3 and the raid1 metadata don't overwrite each other.
This means you'll have 2 overlapping partitions on wd3, one to be used by
raid1 and another one to be used to mount the ffs.

-- 
Manuel Bouyer <bouyer%antioche.eu.org@localhost>
     NetBSD: 26 ans d'experience feront toujours la difference
--