Bug#776676: Alternate way to probe ZFS pool name ?

[h.geoffroy at eden-3d.org]

Dear maintainer & reporter,

As Chris Dos indicated, the second part of this bug (missing pool after 
`ZFS=`)
can be worked around by using `zdb` or `zpool` instead of `grub-probe` 
to read
the pool name. This allows one to boot from a pool with unsupported
  features, using a separate `/boot` partition).

The patch that they linked should fix this part of the problem, and 
allow
  `update-grub2` to run fine on such systems. Personally, I've been 
using
this line in `/etc/grub.d/10_linux` as a workaround :

> rpool=`zdb -l ${GRUB_DEVICE} 2>/dev/null | grep '\sname\:' | awk 
> -F"'" '{print $2}'`

In the case that both solutions are inadapted, I think that the script 
should
provide a default value for `rpool`, such as `rpool`, as there is no 
way
for the pool name to be empty.

Regards;

HG