Bug#990704: Debian's installer's GRUB installer into a new non-primary drive (sdb) makes booting new Debian drive unbootable.
Version: https://gemmei.ftp.acc.umu.se/debian-cd/current/amd64/iso-cd/debian-10.10.0-amd64-netinst.iso and https://gemmei.ftp.acc.umu.se/cdimage/unofficial/non-free/cd-including-firmware/bullseye_di_rc2+nonfree/amd64/iso-cd/firmware-bullseye-DI-rc2-amd64-netinst.iso
Downloaded, mounted, and booted Debian's net installer ISO (e.g.,
into an old 64-bit W7 HPE SP1 VirtualBox v6.1 VM with a brand new virtual SSD (2 virtual drives = 1 old W7 HDD + 1 new
blank SSD). I'm trying it before doing it virtually instead of my real physical PC to learn and practice (don't want to
hose my 12 yrs. old real hardware production PC!). I picked most of Debian's defaults (no GUI packages to install for
now). I'm currently having problems with its GRUB bootloader part.
I told it no to its "Install the GRUB boot loader to your primary drive." (https://i.ibb.co/1b2TYbr/primary.gif) and
picked /dev/sdb (new virtual SSD) as shown in https://i.ibb.co/pRKBjBZ/2SDs.gif. I do NOT want to use its GRUB for dual
booting. I'll manually boot the specific drive to boot its specific OS from BIOS' boot menu. Anyways, it completed. I
told BIOS to boot the new SSD with Debian, but it got stuck with a blank black screen with its blinking _ cursor:
https://i.ibb.co/v4xWdMP/rebooted-Stuck.gif. My 64-bit W7's drive still boots though.
I tried again with Buster v10.10, but got the same exact results. If I tell Debian installer to install its GRUB
bootloader into the primary and /dev/sdb, then it will work but I get W7 in GRUB's boot loader which I don't want.
https://groups.google.com/g/alt.os.linux.debian/c/Ww_-hii7o_Y/m/MUUni-hxAgAJ says Jack was able to reproduce it as well
with his Debian installation, but not with Mint. There seems to be a bug in Debian's installers? :(
Thank you for reading and hopefully answering soon. :)