homelab

Infrastructure

misaki: Montreal Raspberry Pi.

Deploying

Cross-Platform Deploy

Deploying an aarch64 machine from x86_64 requires adding binfmts emulation support:

sudo update-binfmts --package qemu-user-static --remove qemu-aarch64 /usr/bin/qemu-aarch64-static
sudo update-binfmts \
    --package qemu-user-static \
    --install qemu-aarch64 /usr/bin/qemu-aarch64-static \
    --magic '\x7f\x45\x4c\x46\x02\x01\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\xb7\x00' \
    --mask '\xff\xff\xff\xff\xff\xff\xff\x00\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff\xff' \
    --offset 0 \
    --credential yes \
    --fix-binary yes

OSX setup

Set hostname (System Preferences > Sharing).

Install homebrew:

/bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)"

Install nix:

sh <(curl -L https://nixos.org/nix/install)

Until this is addressed: LnL7/nix-darwin#149

sudo mv /etc/nix/nix.conf /etc/nix/.nix-darwin.bkp.nix.conf

Clone repository, then (replace hostname):

nix build .#darwinConfigurations.{hostname}.system

Set up synthetic.conf:

echo "run\tprivate/var/run" | sudo tee -a /etc/synthetic.conf
/System/Library/Filesystems/apfs.fs/Contents/Resources/apfs.util -t

Run:

./result/sw/bin/darwin-rebuild switch --flake .

Bootstrapping Nix on OVH

To install an ephemeral NixOS on OVH, use the following steps:

Reboot the VPS into Rescue Mode and SSH into the node with the provided credentials.
Format the root filesystem (in this example, /dev/sdb is the drive, /dev/sdb1 is the OS partition, and /dev/sdb15 is the EFI partition):
```
apt install btrfs-progs
mkfs.btrfs -f /dev/sdb1
```

Mount the new partitions into /mnt so that a NixOS install can be performed:

mount /dev/sdb1 /mnt
btrfs subvolume create /mnt/nix
btrfs subvolume create /mnt/persist
umount /mnt
mount -t tmpfs -o mode=755 tmpfs /mnt
mkdir /nix /mnt/{boot,nix,persist}
mount /dev/sdb1 -o subvol=nix /mnt/nix
mount /dev/sdb1 -o subvol=persist /mnt/persist
mount /dev/sdb15 /mnt/boot
mount /dev/sdb1 -o subvol=nix /nix

Install Nix and the installation tools into the recovery OS.

groupadd -g 30000 nixbld
useradd -u 30000 -g nixbld -G nixbld nixbld
curl -L https://nixos.org/nix/install | sh
. $HOME/.nix-profile/etc/profile.d/nix.sh
nix-channel --add https://nixos.org/channels/nixos-23.05 nixpkgs
nix-channel --update
nix-env -f '<nixpkgs>' -iA nixos-install-tools
nixos-generate-config --root /mnt

Edit /etc/nixos/configuration.nix to ensure that the OpenSSH server is enabled (services.openssh.enable = true) and set credentials to allow remote access once the system reboots (for example, by setting users.users.root.initialHashedPassword). Ensure that the root tmpfs filesystem has mode=0755 set as an option (otherwise SSH will complain about permissions). If there is an error building the logrotate config, add services.logrotate.checkConfig = false (see here)
Install Nix onto the target drive:
```
nixos-install --root /mnt
```

sciyoshi / homelab