Hi, I have a similar problem with plain grub-pc (no EFI) I use the first two HDD as an MDM array and installed grub on both /dev/sda and /dev/sdb. A few weeks ago the first HDD failed and was replaced, and I used update-grub grub-install /dev/sda afterwards and could reboot the computer without problems. The next reboot after the upgrade to grub 2.04 failed with symbol `grub_file_filters` not found The grub update didn't show anything interesting on the console or dpgk.log The problem appears to be that grub 2.04 uses only devices by disk-id and didn't install on /dev/sda even though grub 2.02 did. Fortunately dpkg-reconfigure grub-pc fixes the calamity. What's the preferred way to reinstall grub on a new disk with 2.04? Preferrably non-interactive/scriptable.
Cheers
