clusev/docker/restart-sentinel

Clusev restart sentinel (host watcher)

One-click stack restart from the dashboard — without giving the container the Docker socket.

How it works

  Dashboard (app container)                     Host
  ─────────────────────────                     ────
  System → "Jetzt neu starten"
        │
        ▼
  DeploymentService::requestRestart()
  writes storage/app/restart-signal/restart.request
        │   (shared bind mount: ./run on the host)
        ▼
  ./run/restart.request appears  ──────────►  systemd clusev-restart.path
                                                    │  (PathExists=)
                                                    ▼
                                              clusev-restart.service (oneshot)
                                                    │  runs watch.sh once
                                                    ▼
                                              docker compose -f docker-compose.prod.yml up -d
                                              rm ./run/restart.request

The app only ever writes a marker file. A scoped host-side systemd unit does the restart. The file content is a non-sensitive ISO timestamp; the trigger is the file existing, not what it holds.

Files

File	Role
watch.sh	The actual logic: once (systemd) restarts the stack + deletes the sentinel; loop is a standalone inotify/poll fallback for hosts without systemd.
clusev-restart.path	systemd .path unit — PathExists= the sentinel, triggers the service.
clusev-restart.service	systemd oneshot — runs watch.sh once.

Install (systemd — preferred)

From the project root (default path /home/nexxo/clusev; adjust the units if yours differs):

sudo cp docker/restart-sentinel/clusev-restart.path    /etc/systemd/system/
sudo cp docker/restart-sentinel/clusev-restart.service /etc/systemd/system/
sudo systemctl daemon-reload
sudo systemctl enable --now clusev-restart.path

Check it:

systemctl status clusev-restart.path
# Trigger a test restart by hand:
touch ./run/restart.request
journalctl -u clusev-restart.service -f

Both units hard-code /home/nexxo/clusev. If your project lives elsewhere, edit PathExists= (in .path), and WorkingDirectory= / Environment=CLUSEV_DIR= / ExecStart= (in .service) before copying. The User= in the service must be able to run docker compose (root, or a member of the docker group).

Install (no systemd — poll/inotify fallback)

Run the watcher as a long-lived loop (e.g. under your own supervisor, tmux, or nohup):

CLUSEV_DIR=/home/nexxo/clusev docker/restart-sentinel/watch.sh loop

It uses inotifywait if available (apt-get install inotify-tools), otherwise polls every CLUSEV_POLL seconds (default 5).

Security note

• The container gets NO Docker socket — it cannot run docker at all. It only writes storage/app/restart-signal/restart.request on a shared bind mount.
• The restart is performed by a scoped host systemd unit (clusev-restart.service), the only component permitted to drive Docker. A panel compromise therefore cannot run arbitrary docker commands — at worst it can request a restart of the same stack.
• watch.sh only deletes the sentinel after a successful docker compose up -d, so a transient failure is retried on the next trigger rather than silently lost.

Config (watch.sh env)

Var	Default	Meaning
CLUSEV_DIR	repo root (resolved from the script path)	dir holding docker-compose.prod.yml
CLUSEV_SIGNAL	$CLUSEV_DIR/run/restart.request	absolute path of the sentinel file
CLUSEV_POLL	5	poll interval (seconds) for the no-inotify loop fallback