Hi Dennis, during the package upgrade of GRUB, `grub-install` uses `ofpathname` to determine the OF path of the device that holds the GRUB files needed for booting and uses `nvsetenv` to write it to the NVRAM. Unfortunately `ofpathname` doesn't return a working OF path on Power Macs. To fix that issue, please check [1]. You need to have `ofpath` available. If you don't have the `yaboot` package installed, you need to get it from snapshots.debian.org ([2]).
The basic process is to use an installer CDROM to boot into rescue mode, chroot into your existing installation, [install yaboot package] and use the commands from [1]: ``` # nvsetenv boot-device "$( ofpath /dev/<HFS_BOOTSTRAP_PARTITION> ),\grub" ``` ...and reboot. Cheers, Frank [1]: https://lists.debian.org/debian-powerpc/2019/04/msg00171.html [2]: http://snapshot.debian.org/archive/debian-ports/20190414T164455Z/pool-ppc64/main/y/yaboot/yaboot_1.3.17-4%2Bports1_ppc64.deb
