Comment 7 for bug 1816240

WRAP UP

First my mistake:
I found a work-around. My 2008 HP dc5850 allows me to boot from the first disk of the internal SATA-2 controller or from a SATA-3 PCIe card, I have added for the SSD. I did boot in the BIOS from the SSD, but did forget all about it and assumed during the installation of Xubuntu with btrfs, that I was still booting from sda. That is where everything started to go wrong, since grub (SSD) still expected the previous ext4 system on that newly installed partition.

Second the remaining bug in update-grub.
I booted in the main system again and did run update-grub. Update-grub did not detect the btrfs system and left it out from the list of bootable system. So in my mind there was no way I could boot that just installed system and that resulted in this bug-report.

I'm lucky with the separate SATA-3 controller, because I can boot both systems, but I have to select the btrfs system from the BIOS after any update of one my three ext4 systems. During 'normal' operation I have to select the boot entry for my main system manually. So it is important, that update-grub is corrected for those people with a BIOS without drive choice.