Flash image to partition, and boot with grub manual entry

How to flash image (.iso) to paritition⌗

1. Create partition

sudo fdisk /dev/sda

[–more–]

2. Format partition

sudo mkfs.ext4 /dev/sda11

3. Write image to partition

sudo dd bs=4M if=/home/stroky/Downloads/cachyos-desktop-linux-241110.iso of=/dev/sda11 status=progress oflag=sync

4. Mount partition

sudo mount /dev/sda11 /mnt/cachyos

5. Check for the grub.cfg in there

ls /mnt/cachyos/boot/grub/

6. Add entry

sudoedit /etc/grub.d/40_custom

There are 3 main ways

• Direct provide path for grub.cfg:

menuentry 'CachyOS Install direct' {
    set root=(hd1,gpt11)
    configfile /boot/grub/grub.cfg
    # linux ($root)/arch/boot/x86_64/vmlinuz-linux-cachyos root=/dev/sda11 ro quiet splash 
    # initrd ($root)/arch/boot/x86_64/initramfs-linux-cachyos.img
}

• Boot through partition:

menuentry 'CachyOS Install dev11' {
    set root=(hd1,gpt11)
    linux ($root)/arch/boot/x86_64/vmlinuz-linux-cachyos root=/dev/sda11 ro quiet splash cow_spacesize=10G
    initrd ($root)/arch/boot/x86_64/initramfs-linux-cachyos.img
}

• Boot through iso:

menuentry 'CachyOS Install' {
    set isofile="/home/stroky/Downloads/cachyos-desktop-linux-241110.iso"
    loopback loop $isofile
    linux (loop)/arch/boot/x86_64/vmlinuz-linux-cachyos img_dev=/dev/sda8 img_loop=$isofile earlymodules=loop cow_spacesize=10G
    initrd (loop)/arch/boot/x86_64/initramfs-linux-cachyos.img
}

Then finally update grub config:

sudo grub-mkconfig -o /boot/grub/grub.cfg

To get the hd1,gpt11 you can go to grub shell and press ls;

Reboot