I had this problem as well with software raid after recent upgrade to Xenial (and then after another update to Xenial packages to 2.02~beta2-36ubuntu1 — however, at about the same time (at least after the last reboot), I've also added lvm-cache to the root partition, and that seems to have been the actual problem.
Latest Xenial grub cannot boot from lvm-cached system/boot (they are one and the same for me) partitions. Workaround: disable caching of the system partition. I'll probably move /boot out into separate partition as well, but thought I'd throw this out as well. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1318568 Title: grub upgrade fails with lvm on top of dmraid To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/grub2/+bug/1318568/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
