On 08/13/2016 08:49 AM, Hendrik Boom wrote:
>
> But grub is such a rat's nest that I worry about getting an
> experimental vdev too early in the boot process to be able to avoid it
> with grub's boot menu.
>
> Is this a real concern?
>
> -- hendrik

That should not be an issue. The grub menu comes before the initrd is
loaded. You could increase the GRUB_TIMEOUT in /etc/default/grub to give
yourself more time to select which installation you want to boot.

Don't let the test installation be the one to rule grub or even be the
default choice in the boot menu. If the test system takes over the
bootloader after installing it, reboot into the first installation and run
grub-install.

Keep a copy of the non-vdev initrd in the test installation, so you can
boot with it if necessary.

-fsr