How do i partition my nvme to dualboot, running arch main system, want windows on it too

[chrome hull]

do i just cut it in half set it as fat32 and select that partition in windows install? how do i manage this

[crisp plinth]

depends on your use case on how much space you would like reserved for windows

[true lotus]

How many GiB do you have? @chrome hull

[crisp plinth]

in any case, you can use gparted on an ubuntu live iso to format your drive to create unallocated space

[idle gulch]

post lsblk -f for context, you left your plan out

.s litany

[coarse glacier]

Please follow the Standard Litany when asking a question:
• What was your environment? What was your operating system, configuration?
• What did you do? What did you run or test? Where?
• What actually happened? What were the exact results, complete log contents, exact error messages?
• What did you expect? What were you aiming to achieve? What result were you looking for?

Vague or superficial questions will yield vague or superficial answers. False information leads to false solutions.

Also see this similar guide on how to ask smart questions.

[chrome hull]

512 gb hdd

i was gonna shrink the ex4 part to 100gb for arch then the other 300 or so for windows

minus the swap and the efi part

[true lotus]

Okay

Can you send lsblk output?

[chrome hull]

the big partition on the 512 gb

[true lotus]

Do you have a backup disk? Because you can't just resize it because Windows assumes it's installing first.

I remember installing Windows 11 after resizing and it straight up decided to delete my first partitions and turn it into EFI 😭

I recommend you to backup the data

and do this

typing wait 😭

/dev/sdX1 |    100M    | EFI System Partition (Windows Boot Partition)
/dev/sdX2 |    16M     | Microsoft Reserved Partition (MSR)
/dev/sdX3 |   307216M  | Microsoft Basic Data (Windows Main Partition)

-- Optional: Delete Windows recovery partition if not needed --

/dev/sdX4 |   1024M     | EFI System Partition (Linux Boot Partition)
/dev/sdX5 |   163856M   | Linux Root (x86-64)  (Linux Root Partition)
/dev/sdX6 | <Remaining> | Linux Swap           (Linux Swap Partition)

Disable or de-rank Windows Boot Manager in your Firmware setup

and enable OSProber in GRUB

[true lotus]

So it asks for GRUB

[true lotus]

This will automatically add a Boot entry for Windows to GRUB

[cedar cedar]

(You can do this using efibootmanager im pretty sure)

[true lotus]

Well, the ideal way is to do it in setup 🤷

Also this only works if it has access to EFIVars, which is enabled by default on Arch but not always

Also bcd from Windows can override efibootmgr, Firmware setup has highest priority so you'd probably wanna do it there

[cedar cedar]

When you say remaining swap you should specify twice the about of RAM they have

[true lotus]

That is outdated, remaining which is supposed to be around 15.9GiB based on his hard drive space is good enough

Twice the amount of RAM is a lot

We have compression

[true lotus]

Even for hibernation

Unless he has more than 16GiB of RAM

[cedar cedar]

Fair enough. So you say he makes all these partitions now in the archiso or just the root partitions of linux and windows then let windows do the rest with the bootloader?

Just trying to understand sorry

[true lotus]

Also @chrome hull you have to install Windows first and then you delete the Recovery Partition and resize Windows and then install Arch with GRUB and OSProber. If you resize any partitions, without backup, you're wrecked, resizing never works perfectly.

[true lotus]

He installs Windows and then modifies the partitions :D

[true lotus]

Look you need to resize it INSIDE Windows, cfdisk or fdisk sometimes won't resize properly

[true lotus]

Layout @chrome hull

I'm gonna go now chat 👋

[chrome hull]

so basically id need to wipe arch with windows and reinstall arch -_-

im unable to do that cant diskpart just take and cut half of the linux partition and reassign it as windows without deleting the arch install

[true lotus]

Why don't you TRY

please backup before you do

[chrome hull]

i cant write over my arch install there is already important files on here