Installing as dual boot with Linux or Windows

The following section will guide you through the steps to install Athena OS as dual booth with Linux or Windows by covering all the possible choices you could set.

Windows pre-settings

In case you are installing Athena OS in dual boot with Windows, make sure that Fast Startup is disabled. For doing that on Windows, open Control Panel -> Hardware and Sound -> Power Options -> click on Choose what the power buttons do on the left side -> click on Change Settings that are currently unavailable on top (This will ask for administrator permissions) -> Unselect the Turn on fast startup option and click on Save Changes button.

Install Athena OS as dual boot

Once prepared the setup as described in Baremetal installation prepare, and rebooted the system with your plugged USB drive containing the Athena OS installation media, according to your boot mode (EFI or BIOS/Legacy), you will be shown:

for EFI boot, select Athena OS install medium or:

for BIOS/Legacy boot, select Boot Athena OS (x86_64, BIOS, open source).

Pre-installation

If you are installing Athena OS along with Windows, you need to preserve the Microsoft bootloader files. We need to face the following scenario:

• Format the existing boot partition: save Microsoft bootloader folder somewhere, format the boot partitition, and move Microsoft bootloader folder inside it.

Save Microsoft bootloader

If you will format the boot partition, you need to save Microsoft bootloader files. Once you land on the Live Environment, open terminal and mount your existing boot partition (i.e., /dev/nvme0n1p1) containing Microsoft bootloader:

sudo mount /dev/nvme0n1p1 /mnt
cp -rf /mnt/EFI/Microsoft ~/
sudo umount /mnt

it will save Microsoft folder in the liveuser home folder. We will restore it just after the Athena OS installation ends as explained later.

Installation

Finally, follow the Aegis TUI Installer chapter until the Partitioning section.

Partitioning

Aegis TUI

If you are using Aegis TUI, on Partitioning, select Manual:

If your system is UEFI, follow EFI section. If your system is BIOS-Legacy, scroll down and follow BIOS-Legacy section below.

EFI

The example partition will appear like:

Select the disk to work on. It is needed now to create the needed partitions for Athena OS. At label selection, select gpt.

First, due to Windows installation, a UEFI boot partition should already exist, so we don’t need to create an EFI partition.

(Optional) In case you want to install a separated EFI partition, select the free space entry, press “New”, otherwise “Delete” or “Resize” an existing partition to get additional free space. As Partition Size, set “512M”, select “Type” option and select “EFI System” as partition type.

(Optional) If you want to set a Swap Partition, if you have enough available free space, press “New”, otherwise “Delete” or “Resize” an existing partition to get additional free space. As Partition Size, set “1G” or “2G” or “4G” or “8G” depending on the amount of your RAM or your preference, select “Type” option and select “Linux swap” as partition type.

Note

If you are going to enable Zram later, you don’t need to create a Swap partition.

Now, create a root partition for your system. If you have enough available free space, press “New”, otherwise “Delete” or “Resize” an existing partition to get space. As Partition Size, set the remaning free space amount. As “Type”, be sure it is set as “Linux filesystem”.

Afterwards, on the menu, select “Write” to apply these changes to your disk. When asked “Are you sure you want to write the partition table to disk?” type yes and press Enter key. Finally, press Quit.

Now it will be asked you to select what is the EFI partition. Select the existing one (usually it should be the one sized 512M):

As EFI partition mountpoint, select /boot and as EFI partition filesystem select fat or vfat.

Now it will be asked you to select what is the root partition you created. Select it (usually it should be the one sized as you set previously):

Then, as root partition mountpoint, select / and as root partition filesystem select one of shown options (i.e., btrfs).

Continue to follow the Partitioning Final Steps.

BIOS Legacy

Select the disk to work on. It is needed now to create the needed partitions for Athena OS. At label selection, select dos.

In a GRUB-BIOS Legacy system, the creation of a boot partition is not needed because it will be created automatically by MBR (dos) in the boot sector.

But, if you need to create an encrypted root partition, you need to create a separated GRUB-BIOS Legacy boot partition. To do this, select the free space entry, press “New”, otherwise “Delete” or “Resize” an existing partition to get additional free space. As Partition Size, set “512M”, select “Type” option and select “Linux” as partition type. Keeping the selection on the created root partition, press on “Bootable” option to mark it as bootable partition. In case you have already an existing GRUB Legacy partition, and you want to use it, then don’t create a new one.

(Optional) If you want to set a Swap Partition, if you have enough available free space, press “New”, otherwise “Delete” or “Resize” an existing partition to get additional free space. As Partition Size, set “1G” or “2G” or “4G” or “8G” depending on the amount of your RAM or your preference, set “primary” and select “Type” option and select “Linux swap” as partition type.

Note

If you are going to enable Zram later, you don’t need to create a Swap partition.

Now, create a root partition for your system. If you have enough available free space, press “New”, otherwise “Delete” or “Resize” an existing partition to get space. As Partition Size, set the remaning free space amountand set it as “primary”. As “Type”, be sure it is set as “Linux”. In case you didn’t create any GRUB Legacy partition because you use the one created automatically by MBR (dos) in the boot sector, keeping the selection on the created root partition, press on “Bootable” option to mark it as bootable partition.

Afterwards, on the menu, select “Write” to apply these changes to your disk. When asked “Are you sure you want to write the partition table to disk?” type yes and press Enter key. Finally, press Quit.

Now it will be asked you to select what is the GRUB partition. Select the existing one (usually it should be the one sized 512M). If you use the GRUB inside the boot sector of the root partition, skip this step by pressing CTRL+C.

As GRUB partition mountpoint, select /boot and as GRUB partition filesystem select ext4.

Now it will be asked you to select what is the root partition you created. Select it (usually it should be the one sized as you set previously):

Then, as root partition mountpoint, select / and as root partition filesystem select one of shown options (i.e., btrfs).

Final Steps

Next it will be asked if you created a Swap partition. If you didn’t create it, press No. If you did, press Yes. It will be asked you to select what is the swap partition you created. Select it (usually it should be the one sized 1G or 2G or 4G or 8G):

Finally, it will be asked if you wish to encrypt the root partition:

Then, continue to follow the Aegis TUI guide.