A self-hosted monitoring dashboard for headless servers.
If you run a Linux box or a Mac mini in a closet somewhere, you know the routine — SSH in, run a handful of commands, try to remember what the disk usage was last time. Sentinel replaces that with a single web page you can pull up from your phone.
It's a Next.js app that runs directly on the machine you want to monitor. It reads system state through standard OS commands, presents it in a clean interface, and refreshes every 10 seconds. No agents to install, no cloud accounts, no data leaving your network.
CPU usage (delta-based, not a snapshot), load average (1/5/15 min), memory with accurate active+wired reporting, swap usage, disk utilization across all mount points, battery health with cycle count and capacity degradation, temperature readings, and top processes ranked by CPU.
LAN IP, external IP (cached, refreshed every 5 minutes), TailScale IP (auto-detected if running), default gateway, DNS servers, network manager, real-time download/upload throughput, all network interfaces with MAC addresses and link status, and every listening port with its process name, PID, and protocol.
A security score (0–100, letter graded A through F) based on firewall status, SSH hardening, auto-update configuration, and installed security tools. Shows active SSH sessions, recent logins with success/failure status, and actionable warnings when something needs attention.
Docker containers with state, image, ports, and uptime. Cron jobs with human-readable schedules. Key system daemons (sshd, docker, tailscaled, nginx, etc.) with running/stopped status.
- System updates — available package count with details (supports apt, yum, brew, softwareupdate)
- System logs — scrollable viewer of recent log entries right on the overview page
- Power actions — reboot and shutdown with double-click confirmation
- Dark and light mode — persistent toggle, follows your preference
- Mobile-friendly — bottom tab bar, responsive tables, works well on phones
Prerequisites: Node.js 18+ and npm, on the machine you want to monitor.
git clone https://github.com/CmdShiftExecute/sentinel.git
cd sentinel
npm install
npm run build
npm startOpen http://localhost:3333. That's it.
For development with hot reload:
npm run devSentinel is meant to run on the server it monitors. Pick whichever method you're comfortable with.
npm install -g pm2
npm run build
pm2 start npm --name sentinel -- start
pm2 save
pm2 startup # generates a command to run — follow its outputCreate /etc/systemd/system/sentinel.service:
[Unit]
Description=Sentinel Dashboard
After=network.target
[Service]
WorkingDirectory=/path/to/sentinel
ExecStart=/usr/bin/npm start
Restart=always
User=your-user
Environment=PORT=3333
[Install]
WantedBy=multi-user.targetsudo systemctl enable --now sentinelIf your server is headless, TailScale is the simplest way to reach the dashboard from your phone or laptop:
# On the server
curl -fsSL https://tailscale.com/install.sh | sh
sudo tailscale up
# From any device on your tailnet
http://<tailscale-ip>:3333Or expose it on your local network and access via the server's LAN IP.
The reboot and shutdown buttons need passwordless sudo for shutdown commands. On your server:
sudo visudoAdd this line (replace your-user with your username):
your-user ALL=(ALL) NOPASSWD: /sbin/shutdown, /usr/bin/systemctl reboot, /usr/bin/systemctl poweroff
Skip this step if you don't need remote power control — everything else works without it.
| Variable | Default | Description |
|---|---|---|
PORT |
3333 |
Server port |
No config files. Sentinel auto-detects your platform (Linux or macOS) and adjusts its data collection accordingly.
To change which system daemons are monitored, edit the svcNames array in src/app/api/system/route.ts:
const svcNames = ["sshd", "docker", "tailscaled", "nginx", "postgres"];| Feature | Linux | macOS |
|---|---|---|
| CPU / Memory / Disk | Yes | Yes |
| Battery & Health | Yes | Yes |
| Temperature | Yes | Partial* |
| Network / Ports | Yes (ss) |
Yes (lsof) |
| Throughput | Yes (/proc/net/dev) |
Yes (netstat) |
| Firewall | UFW, iptables | Application Firewall |
| Docker / Cron | Yes | Yes |
| System Updates | apt, yum | softwareupdate, brew |
| Power Actions | systemctl, shutdown | shutdown |
*macOS temperature reads from the battery sensor. For CPU temperature, install osx-cpu-temp.
| Framework | Next.js 14 (App Router) |
| Language | TypeScript 5 |
| Styling | Tailwind CSS 3.4 with OKLCH color system |
| Charts | Recharts |
| Data Fetching | SWR with 10-second polling |
| Fonts | Bricolage Grotesque + Figtree |
sentinel/
├── src/
│ ├── app/
│ │ ├── api/
│ │ │ ├── system/route.ts # System data collection
│ │ │ └── actions/route.ts # Power actions (reboot/shutdown)
│ │ ├── page.tsx # Overview dashboard
│ │ ├── hardware/page.tsx # CPU, memory, disk, battery, processes
│ │ ├── network/page.tsx # IPs, interfaces, ports, throughput
│ │ ├── security/page.tsx # Score, tools, sessions, logins
│ │ ├── services/page.tsx # Docker, cron, system processes
│ │ ├── layout.tsx # Root layout with sidebar
│ │ └── globals.css # Design tokens (OKLCH)
│ ├── components/
│ │ ├── sidebar.tsx # Desktop sidebar + mobile bottom nav
│ │ ├── gauge.tsx # Animated SVG gauge
│ │ ├── status-badge.tsx # Status indicator badges
│ │ └── theme-toggle.tsx # Dark/light mode toggle
│ ├── hooks/
│ │ ├── use-system-data.ts # SWR data fetching hook
│ │ └── use-theme.ts # Theme persistence hook
│ └── lib/
│ ├── types.ts # TypeScript interfaces
│ └── utils.ts # Formatting utilities
├── package.json
├── tailwind.config.ts
└── tsconfig.json
Contributions are welcome. See CONTRIBUTING.md for development setup and guidelines.
MIT — use it however you want.