name=Matthew%20Campbell&email=trenix25%40pm.me -------- Original Message -------- On Jun 12, 2020, 8:32 PM, elvis < el...@dogonfire.com> wrote:
On 13/6/20 10:58 am, Matthew Campbell wrote: > I hope I don't create a fight with this. > > I booted the Debian netinst disc and installed Linux on /dev/sdb1 as > the root partition. My computer is old. The system BIOS does not see > this hard drive, nor does Grub, but the Linux kernel does. I'm running > the 4.19.0-9-686-pae kernel, #1 SMP Debian 4.19.118-2 and Buster 10.4.0. > > The installation program tried to set up Grub on /dev/sda, but since > Grub cannot see /dev/sdb the system gets stuck in rescue mode. It sees > two hard drives hd0 and hd1, but says both have unknown filesystems. I > had to install Linux on a 32 GB USB flash drive just to get my > computer to boot. Now I can boot Windows again too. The flash drive is > _really_ slow. > > Grub has /dev/sdb1 listed as an option, but says the disk does not > exist and to load the kernel first, which of course is on the new hard > drive partition /dev/sdb1 which I can access just fine after starting > the kernel. The catch is that I have to boot the flash drive /dev/sdc1 > to do so thus making it the root filesystem. > > 1) How can I help Grub see and use /dev/sdb1 ? > > 2) Can I create a CD or USB flash drive with which to boot the > computer so it loads the kernel and mounts /dev/sdb1 as the root file > system? This is what you want. The kernel and initrd can be on a separate partition to the root filesystem. Append root=/dev/sdb1 to change the root from the ramdisk. Or as on my Debian system, it ignores the kernel line and seems to find the root filesystem anyhow. Handy when I mess up the order of the disks and sdc1 becomes sdb1. No idea how it does it, magic I guess. Response: It finds the correct disk/partition because each has a unique identifier UUID which Grub looks for. Grub can't see my /dev/sdb so telling it to boot /dev/sdb1 won't help because it can't see the hard drive. It will claim that the drive or partition does not exist. > > 3) How long is my flash drive likely to last? Will it wear out as I > continue to use it? Will reading from it damage it, or just writing to it? > > 4) How exactly does Grub work? What is the process, step by step? How > do I configure Grub to do what I want? The installation program seems > determined to do everything its own way. > > Thank you for your assistance in these matters. > > name=Matthew%20Campbell&email=trenix25%40pm.me > > > > -- Himself, he never took too seriously. His work most seriously.