[SOLVED] restoring grub for dual boot with windows

Ai_Programmer · 03-03-2019, 11:25 AM

So the instructions from itsfoss worked! I'm now at the grub prompt/cli and found the list of commands but I don't know what to do with it.

colorpurple21859 · 03-03-2019, 12:30 PM

set root=(hd0,4)
linux /vmlinuz root=/dev/sda4
initrd /initrd.img
boot

If it boots run update-grub as root

Ai_Programmer · 03-03-2019, 12:52 PM

So I did that & then I then typed exit it said successful & presented me with my f12 boot menu with 2 identical choices. I hit enter & now my system rebooted to the Acer logo & is stuck there

Ai_Programmer · 03-03-2019, 01:04 PM

Now back at grub this time I did those commands & then ctrl+alt+del & it rebooted to the grub prompt/cli. Is it supposed to reboot automatically after completing these commands?

colorpurple21859 · 03-03-2019, 01:25 PM

I forgot to add the last line
boot
This is assuming debian is on the fourth partition

Ai_Programmer · 03-03-2019, 06:07 PM

It worked thanks!!! Now how do I make windows a choice in grub?

colorpurple21859 · 03-03-2019, 07:48 PM

add this to /etc/grub.d/40_custom then run update-grub

Code:

menuentry 'Windows Boot Manager' {
	set root='hd0,gpt1'
	chainloader /EFI/microsoft/Boot/bootmgfw.efi
}

Ai_Programmer · 03-06-2019, 12:59 AM

So I've been enjoying linux & then had some bad news & forgot about this so sorry about not getting back to this thread.
Apparently I can't get back execute the above instructions because I'm not in the the sudoers file.
I wouldn't have made it this far without you guys

thanks
Nick

colorpurple21859 · 03-06-2019, 04:50 AM

debian doesn't use sudo by default.
use

Code:

su -

and give roots password

Ai_Programmer · 03-06-2019, 06:27 PM

thanks

Ai_Programmer · 03-10-2019, 10:16 AM

While this gave no errors so I thought it worked, I just rebooted my machine which leaves me at the grub cli. I thought the commands in post #47 put those commands to execute automatically every boot, how would we do that?

colorpurple21859 · 03-10-2019, 02:43 PM

At least your not getting a grub-rescue prompt, at the grub cli what is the output of

Code:

set

Set will tell you were grub is looking for the grub.cfg file. It can be changed at the grub cli by something along the lines of

Code:

configfile (hd0,1)/ubunut/grub.cfg

or

Code:

configfile (hd0,4)/boot/grub/grub.cfg

Ai_Programmer · 03-11-2019, 10:57 AM

Output of set:
The second command cleared the screen/cli
But configfile (hd0,4)/boot/grub/grub.cfg brought up a graphical grub.

Isn't this the rescue grub? :

Code:

grub>

It's what I see when I boot

Thank you for bringing me this far

colorpurple21859 · 03-11-2019, 12:17 PM

Quote:

Isn't this the rescue grub? :
Code:
grub>
It's what I see when I boot

no, that just means either the grub.cfg doesn't exist, is in the wrong location, or grub bootloader is looking in wrong place.
rescue grub will look something like this :

Code:

grub rescue>

With your debian setup normally the set command prefix will be

Code:

prefix=(hd0,gpt4)/boot/grub

not

Code:

prefix=(hd0,gpt1)/boot/grub

If you copy the /boot/grub/grub.cfg on your root partition to /boot/grub/grub.cfg on your first partition(/dev/sda1) will fix it for the time being, with something like this:
run as root

Code:

mount /dev/sda1 /mnt
cp /boot/grub/grub.cfg  /mnt/boot/grub/grub.cfg

To determine a more permanent solution post your /etc/fstab and /etc/default/grub

Ai_Programmer · 03-12-2019, 01:50 PM

Permission denied:

Code:

nick@debian:~/tor-browser_en-US$ mount /dev/sda1 /mnt
mount: only root can do that
nick@debian:~/tor-browser_en-US$ sudo mount /dev/sda1 /mnt
[sudo] password for nick: 
nick@debian:~/tor-browser_en-US$ cp /boot/grub/grub.cfg /mnt/boot/grub/grub.cfg
cp: failed to access '/mnt/boot/grub/grub.cfg': Permission denied
nick@debian:~/tor-browser_en-US$ sudo mount /dev/sda1 /mnt
mount: /dev/sda1 is already mounted or /mnt busy
       /dev/sda1 is already mounted on /boot/efi
       /dev/sda1 is already mounted on /mnt
nick@debian:~/tor-browser_en-US$ cp /boot/grub/grub.cfg  /mnt/boot/grub/grub.cfg
cp: failed to access '/mnt/boot/grub/grub.cfg': Permission denied