infrastructure/hosts/phoenix.lewd.wtf/services/zfs.nix

{ config, pkgs, ... }:
let
  sendEmailEvent = { event }: ''
    printf "Subject: phoenix ${event} ''$(${pkgs.coreutils}/bin/date --iso-8601=seconds)\n\nzpool status:\n\n''$(${pkgs.zfs}/bin/zpool status)" | ${pkgs.msmtp}/bin/msmtp -a default ciapa@lewd.wtf
  '';
in
{
  # ZFS remote unlocking
  boot.initrd.systemd.enable = true;
  boot.initrd.availableKernelModules = [ "igb" ];
  boot.kernelParams = [
    "ip=192.168.0.42::192.168.0.1:255.255.252.0:phoenix-initrd:eno2:off:192.168.0.1"
  ];
  boot.initrd.systemd.services.zfsunlock = {
    description = "Unlock ZFS pools";
    wantedBy = [
      "initrd.target"
    ];
    before = [
      "zfs-import-zroot.service"
    ];
    unitConfig.DefaultDependencies = "no";
    serviceConfig.Type = "oneshot";
    script = ''
      cat <<EOF > /root/.profile
      if pgrep -x "zfs" > /dev/null
      then
        zfs load-key zroot
        zpool import -f zbigdata
        zfs load-key zbigdata
        zpool import -f zvault
        zfs load-key zvault
        killall zfs
      else
        echo "zfs not running -- maybe the pool is taking some time to load for some unforseen reason."
      fi
      EOF
    '';
  };
  boot.initrd.network = {
    enable = true;
    ssh = {
       enable = true;
       port = 2222;
       hostKeys = [
         /boot-1/initrd-ssh-key
         /boot-2/initrd-ssh-key
       ];
       authorizedKeys = config.users.users.root.openssh.authorizedKeys.keys;
    };
  };

  # ZFS options from https://nixos.wiki/wiki/NixOS_on_ZFS
  networking.hostId = "42069420";
  boot.supportedFilesystems = [ "zfs" ];

  # ZFS notifications
  services.zfs.zed.enableMail = true;
  services.zfs.zed.settings = {
    ZED_EMAIL_ADDR = [ "ciapa@lewd.wtf" ];
    ZED_EMAIL_OPTS = "-a 'FROM:phoenix@lewd.wtf' -s '@SUBJECT@' @ADDRESS@";
    ZED_NOTIFY_VERBOSE = true;
  };

  # Timed status mails (Boot, Shutdown, Weekly)
  systemd.services."boot-mail-alert" = {
    wantedBy = [ "multi-user.target" ];
    after = [ "network-online.target" ];
    wants = [ "network-online.target" ];
    serviceConfig = {
      Type = "oneshot";
      RemainAfterExit = true;
    };
    script = sendEmailEvent { event = "just booted"; };
  };
  systemd.services."shutdown-mail-alert" = {
    wantedBy = [ "multi-user.target" ];
    after = [ "network-online.target" ];
    wants = [ "network-online.target" ];
    serviceConfig = {
      Type = "oneshot";
      RemainAfterExit = true;
    };
    script = "true";
    preStop = sendEmailEvent { event = "is shutting down"; };
  };
  systemd.services."weekly-mail-alert" = {
    serviceConfig.Type = "oneshot";
    script = sendEmailEvent { event = "is still alive"; };
  };
  systemd.timers."weekly-mail-alert" = {
    wantedBy = [ "timers.target" ];
    partOf = [ "weekly-mail-alert.service" ];
    timerConfig.OnCalendar = "weekly";
  };
}