re: raidframe and gpt

[matthew green <mrg%eterna23.net@localhost>]

Paul Goyette writes:
> Does anyone have an example of how to configure raid0 on a GPT disk?

these are my notes i refer to every so often:

https://www.netbsd.org/~mrg/gpt-raid-setup.txt

it's gpt on each with type raid, which gives you dkN @ diskN,
you then create a raid with those dkNs, and then you create
another gpt on the raid device itself, with a ffs partition.

(see below; but skip the raidN.conf method, and just use the
newer raidctl create.)

> I can easily set the partition type with gpt, but how do I reserve
> space for the raid component label?  Do I need to reserve that space?

note how i pick "-b 128" above to get my partitions aligned on
at least 64K bounaries.  nvme/sata probably wants higher (check
your disk specs, it can vary a lot, and you could go as high as
6MB alignment to catch all known alignment...)

> Also, does raidframe understand the NAME=gpt-label syntax in the
> config file?  Or does it require me to specify the particular dk<n> ?
> (And what happens if something moves and <n> changes?)

NAME= works.  use autoconfig raid.. actually just use the new
in -current "raidctl create", since it does all the intro set
and good default choices.

> It seems so much simpler to use ccd(4) but there's a nasty memory
> allocation bug which makes it unuseable for now.

you can't root-on-ccd like you can root-on-raidframe :-)  you
could, using the same initrd method root-on-cgd uses.


.mrg.