live-cd install to flash drive renders NVME Ubuntu install unbootable

[Bob Wheater]

I have Ubuntu 20.4.4 zfs installed on a NVME drive. I was trying to use the live-cd to install another copy of Ubuntu (full install) onto a flash drive. The installation went ahead successfully but when trying to reboot it hung and I had to restart the computer after 30 minutes. However, when I restarted the computer the installation on the NVME drive was unbootable.

Apparently, the live-cd overwrote the grub configuration on the NVME drive. The only way to recover from this is to drop to the command line in grub and issue the the commands described on this web page:
https://askubuntu.com/questions/1225751/recovering-a-borked-grub-with-a-ubuntu-19-10-zfs-root-filesystem

Then run update-grub.

The evidence for this is the following two lines in the fstab on the flash drive.
/boot/efi was on /dev/nvme0n1p1 during installation
UUID=1887-580A /boot/efi vfat umask=0022,fmask=0022,dmask=0022 0 1

The correction to fstab on the flash drive was the following:
# update to point to flash drive
UUID=91EF-3687 /boot/efi vfat umask=0022,fmask=0022,dmask=0022 0 1

Also this recovery procedure from the Grub command line would be easier of grub could read zfs partition instead of saying it is a unknown file system

Also, there is no reason for the live-cd to access any other drive than the one that it is installing on -- this is required for a safe installation procedure.

Note: attached file contains configuration of my system after fstab on the flash drive was fixed to point to correct drive.

Regards,
Bob Wheater

[Ubuntu Foundations Team Bug Bot (crichton)]

Thank you for taking the time to report this bug and helping to make Ubuntu better. It seems that your bug report is not filed about a specific source package though, rather it is just filed against Ubuntu in general. It is important that bug reports be filed about source packages so that people interested in the package can find the bugs about it. You can find some hints about determining what package your bug might be about at https://wiki.ubuntu.com/Bugs/FindRightPackage. You might also ask for help in the #ubuntu-bugs irc channel on Libera.chat.

To change the source package that this bug is filed about visit https://bugs.launchpad.net/ubuntu/+bug/1979852/+editstatus and add the package name in the text box next to the word Package.

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