Re: gptmbr.bin vs RAIDframe

[Stephen Borrill <netbsd%precedence.co.uk@localhost>]

On Tue, 16 Jun 2015, David Brownlee wrote:
> On 16 June 2015 at 14:14, Stephen Borrill <netbsd%precedence.co.uk@localhost> wrote:
> > I've been testing out wedges combined with RAIDframe on HDDs > 2TB. I have:
> > # gpt show wd1
> >        start        size  index  contents
> >            0           1         PMBR
> >            1           1         Pri GPT header
> >            2          32         Pri GPT table
> >           34    20972448      1  GPT part - NetBSD RAIDFrame component
> >     20972482    20972448      2  GPT part - NetBSD RAIDFrame component
> >     41944930  5818588205      3  GPT part - NetBSD RAIDFrame component
> >   5860533135          32         Sec GPT table
> >   5860533167           1         Sec GPT header
>
>
> I'd be wary of starting a partition at 34 (not 4K aligned) for
> performance reasons

Sure, in production I'd do exactly the same. This was just to test out the 
concepts.

> > (wd2 is same)
> > I've then set up 3x RAIDframe RAID1 on the 3 wedges from each disk.
> > raid0 and raid1 (from the wedges with indices 1 and 2) are used directly (i.e. /dev/raid0a is root). There's another GPT on raid2:
> > # gpt show raid2
> >        start        size  index  contents
> >            0           1         PMBR
> >            1           1         Pri GPT header
> >            2          32         Pri GPT table
> >           34  5818587965      1  GPT part - NetBSD FFSv1/FFSv2
> >   5818587999          32         Sec GPT table
> >   5818588031           1         Sec GPT header
> >
> > and I've named this "usr". My fstab contains the following and all is well:
> > /dev/raid0a     /       ffs     rw               1 1
> > /dev/raid1a     none    swap    sw,dp
> > NAME=usr        /usr    ffs     rw               1 2
> >
> > This copes with missing components and wedges being renumbered.
> >
> > The only missing part is trying to make the system directly bootable. I tried "gpt biosboot -i 1 wd0" which didn't give any errors, but equally didn't work. At boot time gptmgr prints "Missing OS" which appears to be because it cannot locate the 0xaa55 signature.
>
> I've also not been able to make a raid-on-wedge partition bootable. I
> think the bootloader needs to be taught another variant of 'skipping
> raidframe header'...

jakllsch@ pointed out off-list that in addition to "gpt biosboot -i 1 wd0",
I also needed to run installboot on the wedge containing raid0 (i.e. 
root). Therefore I ran "installboot /dev/rdk0 /usr/mdec/bootxx_ffsv2"
(and the same on dk3) and it now boots.

--
Stephen