Re: [PATCH] Enable `grub-probe -t device' resolution on ZFS

[Robert Millan]

2010/7/30, Seth Goldberg <address@hidden>:
>
>   You need to ensure that the deivce given isn't degraded.  It's certainly
> possible to boot with a mirrored root with one device degraded.  If you
> choose
> that device for grub-setup, you may fail to write to it or you may succeed,
> but something else may prevent it from being accessible on boot.

I don't think this is the appropiate place for this kind of sanity
check.  Keep in
mind "grub-probe -t device" has many purposes, and for some of them (e.g.
determining the partmap) the ZFS status is irrelevant.

Another codepath (e.g. "grub-probe -t fs") includes this kind of functionality;
it verifies that the requested file will later be readable by GRUB (and IIRC
compares the result).  I think this kind of verification would be
suitable there,
but then, maybe the notion that GRUB can correctly read the file (regardless
on array degradation) is enough.

As for grub-setup, I haven't studied this use case, as I don't currently plan on
implementing it myself, at least not yet (I'm happy with filesystem-agnostic
grub-setup for now).