This bug was fixed in the package grub-installer - 1.128ubuntu8
--------------- grub-installer (1.128ubuntu8) zesty; urgency=medium
* Fix a typo in PReP bootdev selection code; we should not skip over a valid mpath device in favor of the underlying block device, since it won't be available for grub-install later. (LP: #1681932)
-- Mathieu Trudel-Lapierre <email address hidden> Tue, 11 Apr 2017 16:21:30 -0400
This bug was fixed in the package grub-installer - 1.128ubuntu8
---------------
grub-installer (1.128ubuntu8) zesty; urgency=medium
* Fix a typo in PReP bootdev selection code; we should not skip over a valid
mpath device in favor of the underlying block device, since it won't be
available for grub-install later. (LP: #1681932)
-- Mathieu Trudel-Lapierre <email address hidden> Tue, 11 Apr 2017 16:21:30 -0400