NixOS Setup Guide

OS Installation

Boot

1. Insert the NixOS USB into the PC:

   • Make sure the USB is inserted properly before booting.

2. Boot from USB:

   • Go to the BIOS and ensure the PC is set to boot from the USB drive.

3. Boot into NixOS:

   • Once prompted, select the option to boot into NixOS from the USB.

4. Set a temporary password:

   • Once NixOS is running, set a password to enable remote access via SSH. Run the following command in the terminal:

     passwd

   • Follow the prompts to set a password. This password will be used later for SSH access.

5. Find the PC’s IP address:

   • Run the following command to find the PC’s IP address:

     ip addr show

   • Note down the IP address, which you’ll use to connect via SSH.

6. Connect remotely via SSH:

   • From another computer on the same network, connect to the PC using the following command (replace IP with the actual IP address of the PC):

     ssh nixos@IP

   • Use the password you just set when prompted.

Install

Copy and paste the following in the terminal to start the installation process.

sudo bash -c '
# Detect the main drive (largest, non-removable drive)
MAIN_DRIVE=$(lsblk -nd -o NAME,SIZE,TYPE | grep -Ev "loop|rom" | sort -k2 -h | tail -1 | awk "{print \"/dev/\" \$1}")

# Determine if the main drive is NVMe or not
if [[ "$MAIN_DRIVE" == *nvme* ]]; then
  PART1="${MAIN_DRIVE}p1"
  PART2="${MAIN_DRIVE}p2"
else
  PART1="${MAIN_DRIVE}1"
  PART2="${MAIN_DRIVE}2"
fi

(
echo g                        # Create a new GPT partition table
echo n                        # New partition (EFI)
echo 1                        # Partition number 1
echo                          # Default - start at beginning of disk
echo +512M                    # 512 MB EFI partition
echo t                        # Change type
echo 1                        # Set type to EFI System
echo n                        # New partition (Root)
echo 2                        # Partition number 2
echo                          # Default - start immediately after previous partition
echo                          # Use remaining space
echo w                        # Write changes
) | fdisk "$MAIN_DRIVE"       # Run fdisk on the detected main drive

# Reload partition table to recognize new partitions
partprobe "$MAIN_DRIVE"

# Format the partitions
mkfs.fat -F 32 "$PART1"       # Force format EFI partition as FAT32
mkfs.ext4 -F "$PART2"         # Force format root partition as ext4

# Mount the partitions
mount "$PART2" /mnt           # Mount root partition
mkdir -p /mnt/boot            # Create boot directory
mount "$PART1" /mnt/boot      # Mount EFI partition

# Set secure permissions on /boot
chmod 700 /mnt/boot           # Restrict access to /boot

# Generate NixOS configuration
nixos-generate-config --root /mnt

# Insert SSH and firewall settings into configuration.nix
sed -i "/^}$/i \
  services.openssh = {\n\
    enable = true;\n\
    settings.PermitRootLogin = \"no\";\n\
    settings.PasswordAuthentication = true;\n\
  };\n\
  networking.firewall.allowedTCPPorts = [ 22 ];\n\
  users.users.nixos = {\n\
    isNormalUser = true;\n\
    extraGroups = [ \"wheel\" ];\n\
    password = \"password\"; # Set a default password (replace as needed)\n\
  };" /mnt/etc/nixos/configuration.nix

# Install NixOS
nixos-install

# Set the root password non-interactively
echo "root:root" | chroot /mnt chpasswd

# Unmount and reboot
umount -R /mnt
reboot
'

OS Configuration

1. Remove known_hosts (if necessary):
2. Reconnect via SSH:
   • Connect to the newly installed NixOS system:

     ssh nixos@IP

   • Use the password you set during the installation process.

Once connected via SSH, proceed with the NixOS configuration. Copy and paste the following command to start the configuration process:

DNS Setup

sudo bash -c ': > /etc/nixos/configuration.nix && \
curl -L https://raw.githubusercontent.com/davidgatti/nixos_setup/main/server/dns.nix -o /etc/nixos/configuration.nix && \
nixos-rebuild switch && \
cat ~/.config/code-server/config.yaml'

HomeLab Setup

sudo bash -c ': > /etc/nixos/configuration.nix && \
curl -L https://raw.githubusercontent.com/davidgatti/nixos_setup/main/server/home_lab.nix -o /etc/nixos/configuration.nix && \
nixos-rebuild switch && \
cat ~/.config/code-server/config.yaml'

User Configuration

curl -L https://raw.githubusercontent.com/davidgatti/nixos_setup/main/user/home.nix -o ~/.config/home-manager/home.nix && \
home-manager switch

🧐 F.A.Q

• sudo nixos-rebuild switch -I nixos-config=./configuration.nix