On 2020-06-12 17:58, 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.
Computer make and model? Processor? RAM module quantity, size, and
slot? HDD makes, models, interfaces, and sizes? Optical drive
supported media?
The system BIOS does not see this hard drive, nor does Grub, but the Linux kernel does.
Please post the BIOS/CMOS Setup configuration variable names, available
options, and current values for anything related to drives, boot order,
etc..
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.
Which device (/dev/sda or /dev/sdb) is Windows and which is Debian?
Where do the names 'hd0' and 'hd1' come from?
What is the make and model of your USB flash drive?
Are you using a USB 2.0 port or a USB 3.0 port?
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.
I have always installed GRUB to a drive device node -- e.g. /dev/sda --
and never to a partition device node -- e.g. /dev/sdb1.
How do you boot the USB flash drive?
1) How can I help Grub see and use /dev/sdb1 ?
What you are attempting is called "dual-boot". I avoid that. I install
one small SSD in each computer and install one operating system. My
servers have large HDD's in RAID. One server has the bulk of my data
(download, music, pictures, video, etc.). I installed Samba and use it
as a file server for my LAN.
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?
That is possible, but the above is better.
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?
I use SanDisk Ultra Fit USB 3.0 16 GB flash drives for live drives. I
have also used them as system drives in the past. I like the small form
factor that does not stick out (and get broken off), but they run hot
and are not very fast. The interactive user experience can be choppy,
especially if multiple processes write to the flash drive at the same
time. None have died yet, but macOS Time Machine smoked (!) a 128 GB
drive after about a year.
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.
I set up my machines so that the system drive is /dev/sda. I configure
the Debian Installer to install GRUB there.
If you want to learn more about GRUB:
1. Enter the command 'apropos grub' and then read the listed manual pages.
2. Read the Debian Installation Guide:
https://www.debian.org/releases/stable/installmanual
3. Use a search engine to find additional information, such as the GRUB
project site:
https://www.gnu.org/software/grub/
4. Read the source code.
Thank you for your assistance in these matters.
YW. :-)
David