Watchflare: Self-Hosted Host Monitoring

Watchflare is a self-hosted platform that monitors your hosts and tracks their software. It collects system metrics in real time — CPU, memory, disk, network, and temperatures — and maintains a full package inventory across your fleet: installed versions, daily change history, and available updates.

No cloud dependency. No data leaving your infrastructure.

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Two components

Watchflare is made of two pieces that work together:

Hub — the central server. Deploy it once with Docker Compose or as a native Linux binary. It receives data from agents, stores it in a time-series database, and serves the web dashboard. The Hub is a single binary with the frontend embedded.

Agent — a lightweight daemon that runs on each host you want to monitor. Supports Linux and macOS — Windows support is planned. It collects system metrics every 30 seconds, sends a heartbeat every 5 seconds, and builds a daily package inventory. The agent uses minimal resources and runs as an unprivileged system user.

  your-server-1          your-server-2          your-server-3
  [ Agent ]              [ Agent ]              [ Agent ]
      |                      |                      |
      └──────────────────────┴──────────────────────┘
                             |
                         gRPC / TLS
                             |
                          [ Hub ]
                        dashboard + DB

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What it monitors

| Category | Metrics | |----------|---------| | CPU | Usage %, iowait, steal (VMs), temperature (physical hosts) | | Memory | Used, available, buffers, cached, swap | | Disk | Total, used, read/write throughput | | Network | Inbound/outbound bandwidth | | System | Uptime, load average (1/5/15 min), process count | | Containers | Per-container CPU, memory, network (Docker/Podman) | | Packages | Installed packages, versions, outdated detection — ~30 supported package managers |

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What you get

• Real-time dashboard — host status updates within 5 seconds via Server-Sent Events. No polling, no page refresh.
• Historical charts — metrics stored in TimescaleDB with automatic aggregation. View 1h, 12h, 24h, 7d, and 30d time ranges.
• Package inventory — full list of installed packages on every host, updated daily, with change history and outdated package detection.
• Alerts — threshold-based alerts on CPU, memory, and disk, plus host offline notifications delivered to any of the 26+ services supported by Shoutrrr (Discord, Slack, Telegram, Matrix, Ntfy, Gotify, SMTP, generic HTTP, and more).
• Write-Ahead Log — if the Hub is unreachable, the agent buffers metrics locally and replays them on reconnect. Metrics are not lost during brief outages — the WAL holds up to 10 MB by default (configurable via wal_max_size_mb).

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Self-hosted, by design

Watchflare runs entirely on your infrastructure. The Hub and its database live on a server you control. Agents communicate only with your Hub — no external services, no telemetry.