2025-07-17 18:10:37 +02:00

89 lines
2.8 KiB
Nix

{pkgs, lib, ...}:
let
snapshotsDir = "/snapshots/home";
in
{
environment.systemPackages = with pkgs; [
restic
btrbk
libnotify
];
# btrbk systemd service and timer for daily home snapshots
systemd.services.btrbk-home-snapshot = {
description = "Create daily btrbk snapshot of the home subvolume";
serviceConfig = {
Type = "oneshot";
User = "remy";
ExecStartPre = "${lib.getExe pkgs.libnotify} \"Backup\" \"Creating BTRBK snapshot of /home.\"";
# run the btrbk command as superuser
ExecStart = "+${lib.getExe pkgs.btrbk} -c /etc/btrbk/home.conf run";
Environment = "DBUS_SESSION_BUS_ADDRESS=unix:path=/run/user/1000/bus"; # ensure the notification is sent to the correct display
ExecStartPost = "${lib.getExe pkgs.libnotify} \"Backup\" \"Snapshot of /home created successfully.\"";
};
};
systemd.timers.btrbk-home-snapshot = {
enable = true;
description = "Daily timer for btrbk home snapshot";
wantedBy = [ "timers.target" ];
timerConfig = {
OnCalendar = "*-*-* 12:00";
Persistent = true; # ensures missed runs are triggered after resume
};
};
# ensure the target directory exists
systemd.tmpfiles.settings = {
"btrbk snapshots" = {
"${snapshotsDir}" = {
d = {
group = "root";
user = "root";
mode = "0770";
};
};
};
};
# btrbk config for home snapshots
environment.etc."btrbk/home.conf".text = ''
timestamp_format long
# keep snapshots for 2 days independently of the call
snapshot_preserve_min 2d
# retain daily snapshots for 14 days
snapshot_preserve 14d
subvolume /home
snapshot_dir ${snapshotsDir}
'';
# Now create a restic backup off the newest btrbk snapshot
systemd.services.restic-backup-latest-snapshot = {
description = "Backup home subvolume using restic";
serviceConfig = {
Type = "oneshot";
ExecStart = "${lib.getExe pkgs.restic} -r /home/snapshots/restic-backup backup /home/snapshots/home-$(date +%Y-%m-%d_%H-%M-%S)";
# send a notification when the service is done
ExecStartPost = "su remy -c 'notify-send \"Restic Backup\" \"Home backup created successfully.\"'";
};
};
# # the udev rule:
# services.udev.extraRules = ''
# ACTION=="add", SUBSYSTEM=="block", ENV{ID_FS_LABEL}=="backup-restic", TAG+="systemd", ENV{SYSTEMD_WANTS}="backup-restic.service"
# '';
# # the systemd service:
# systemd.services.backup-restic = {
# description = "Backup using restic (triggered when USB drive is plugged in)";
# after = [ "local-fs.target" ];
# wantedBy = [ "multi-user.target" ];
# serviceConfig = {
# Type = "oneshot";
# # TODO: adapt command
# ExecStart = "${lib.getExe pkgs.restic} backup /home/username";
# };
# };
}