how to replace the existing fedora install with existing arch install without breaking stuff

[limpid rain]

okay so I have Arch and Fedora on the same system, GRUB2 was installed by Fedora, I now want to replace my Fedora install in /dev/sda with Arch but I don't want to break grub, what should I do?

[heavy goblet]

Is this a BIOS system?

[limpid rain]

UEFI but the firmware is so garbage it won't boot Linux without BIOS mode

so assume it's BIOS

feel free to ping me when anyone finds a solution

[limpid rain]

I need to install a bootloader basically, but neither grub-install nor grub2-install is being helpful

[limpid rain]

How do I install grub?

[limpid rain]

Yeah I can't install grub

[heavy goblet]

What's not working?

[limpid rain]

It won't be rendered as a separate bootable disk

Shouldn't that happen

I want to make sure I have two drives can be bootable individually

Before dd'ing something

I don't wanna break anything that works smh

Okay lemme dd it

I'm dding it

[heavy goblet]

If you're wiping sda, the GRUB on that will be broken

or just wiped

[limpid rain]

It will be wiped

What do I do after yhat

I'm scared

[heavy goblet]

Wouldn't you just process with the arch installation?

[limpid rain]

Yes

Well after the bootloader is wiped I need to install it again

Now I need to learn how to install it

[heavy goblet]

For BIOS you'll just run grub-install /dev/sda later during the installation

and then generate the config

[limpid rain]

It says "no error reported" but it is not listed 😭

in the system boot menu

[heavy goblet]

I'm confused, have you already setup Arch?

[limpid rain]

Yes, but without bootloader

I used the pre-existing grub on Fedora

@heavy goblet

[heavy goblet]

So the drive just doesn't appear in your boot order?

[limpid rain]

It doesn't

[limpid rain]

Okay so I have this now

[heavy goblet]

You didn't generate the GRUB config

[limpid rain]

I'm doing that now

Is grub-mkconfig syntax the same as grub2-mkconfig?

It runs on /dev/sdb but not /dev/sda

heyy at least I can boot now

lool

only /dev/sdb though 😔

[limpid rain]

I did?

[heavy goblet]

You get that when there isn't a config

[limpid rain]

I am back to the grub console, false alarm

Well I may have accidentally ran swapon /dev/sda2

is that the mistake?

What do I do now?

[heavy goblet]

is sda2 a swap partition?

[limpid rain]

i didn't know

but yes I touched the thing that was already working

Well it's supposed to have the same layout as /dev/sdb

[heavy goblet]

What's on sdb anyway?

[limpid rain]

An arch installation that worked

[heavy goblet]

Is this still the partition scheme you're using?

[limpid rain]

yes

now I copied the working partition and it also works now

/dev/sda3 on / type ext4 (rw,relatime)

I did it

thank you @heavy goblet

[next epoch]

mederp received a thank you cookie!

[sharp shale]

(assuming that you have a separate boot partition) get the partition UUID of your existing root partition. format the root partition, install arch, during the installation, set your existing home partition for use in /home and then do https://www.tecmint.com/change-uuid-of-partition-in-linux/ to change the partition UUID of your drive back to what your old root partition had.

I think this should work

Edit: Maybe kernel loading could be an issue, I don't know. I have never done that before

[weary belfry]

I found that I could get a Toshiba with UEFI to boot with acpi_backlight=vendor

Can't tell if the UEFI implementation sucked or the radeon driver sucks

but it only affects C855D so

[limpid rain]

Thanks @weary belfry, @sharp shale and @heavy goblet but I finally solved it, anyways I'm going to sleep happily now

[next epoch]

smu1zel, ultrablack_, and mederp received a thank you cookie!

[limpid rain]

:3

[weary belfry]

Oh ok that's fine

[sharp shale]

huh ok

[limpid rain]

My issue was with the config file

Mainly

[wintry otter]

can i have the wallpaper please
its co cute