glances-rs

A Linux system monitor in one static binary. CPU, memory, load, network, disk, sensors, processes and alerts — via dashboard, REST, SSE, MCP, CSV, or JSON. A from-scratch port of Glances in pure standard-library Rust.

→ Live site · About · Docs · Source

First principles

A system monitor reads numbers the kernel already publishes (/proc, /sys, sockets) and shows them to a human or ships them to another tool. That is the whole job. Everything else — plugins, servers — is delivery.

Python Glances does this job with an interpreter, a web framework, and a dozen exporter libraries. glances-rs keeps the same architecture, plugin model, and CLI surface, but the dependency graph is empty: one stripped executable, no interpreter, no site-packages, nothing to audit upstream.

Zero trust

The monitor is read-only, but it still listens on ports and parses input. Every row below names something untrusted and what the code does about it.

Distrusted input	Defense
Crate supply chain	No [dependencies] at all — enforced by a build-time lint. There is nothing upstream to compromise.
Memory safety	unsafe only under src/platform/linux/, one portable syscall per block, allowlisted by lint.
Subprocess injection	no_shell lint: Command with explicit argv only, never sh -c.
Paths from flags/config	PathBuf::join only; no format!-built paths.
HTTP exposure	Server binds 0.0.0.0:61208 — put it on a public network only with auth enabled (--password, a password file, or GLANCES_API_KEY). No built-in TLS; terminate behind nginx/Caddy.
Password handling	--password and -u never take argv values (they leak via ps); credentials come from stdin prompts or the 0600 password file.

Install

curl -fsSL https://raw.githubusercontent.com/UberMetroid/glances-rs/rust/install.sh -o install.sh
sh install.sh

The installer verifies its own SHA-256 against the published install.sh.sha256, then drops the binary into ${XDG_BIN_HOME:-$HOME/.local/bin}. Afterwards:

export PATH="$HOME/.local/bin:$PATH"
glances-rs --version

Lock it down at install time (blank = open):

GLANCES_API_KEY=$(openssl rand -hex 32) sh install.sh

Saves the key 0600 to ~/.config/glances/api-key (or $XDG_CONFIG_HOME); glances-rs -w then requires X-API-Key on every data route. Reinstalls keep an existing file; delete it to reopen. A GLANCES_API_KEY in the launch environment overrides the file.

From source instead:

git clone https://github.com/UberMetroid/glances-rs.git
cd glances-rs
cargo build --release
./target/release/glances-rs --help

Needs Rust 1.98.1 or newer.

Or run the distroless container (same binary, host-PID view):

podman build --format docker -t glances-rs:0.10.84 -f install/docker/Containerfile .
podman run -d --name glances-rs --pid=host --net=host \
  -v /sys:/sys:ro -v /:/host:ro -e GLANCES_ROOTFS=/host \
  --device nvidia.com/gpu=all \
  -v /usr/bin/nvidia-smi:/usr/bin/nvidia-smi:ro \
  glances-rs:0.10.84 -w

• --pid=host + --net=host: the monitor sees host processes and serves the host's port 61208 directly.
• -v /:/host:ro + GLANCES_ROOTFS=/host: filesystems report the host mounts, not container overlay.
• --device nvidia.com/gpu=all plus the nvidia-smi bind: live NVIDIA util/VRAM/temperature (needs the NVIDIA container toolkit CDI spec on the host; without it those fields read Null).
• Per-process disk I/O needs to read other processes' counters: a rootless container only sees its own processes (the rest read —); run as root for the full column.
• -e GLANCES_KWH_RATE=0.08: your electricity price in dollars per kWh — enables the dollars-per-month figure in the Power section (or set [power] kwh_rate in glances.conf; the env var wins).
• -e GLANCES_PUBLIC_API=http://api.ipify.org: opt-in public IP lookup (refreshed every 5 minutes by a background thread; blank = off, https refused).
• Container files live in install/docker/; .containerignore stays at the repo root because podman only reads it from the build context.
• Releases: push a vX.Y.Z tag and the release workflow builds, smokes, and pushes ghcr.io/ubermetroid/glances-rs:X.Y.Z plus :latest (Unraid installs from :latest).

Run

glances-rs --stdout-json --stop-after 1   # one JSON snapshot to stdout
glances-rs -w                             # HTTP server: REST + SSE + UI on 61208
glances-rs -c 192.168.1.10 --snmp-force --snmp-community public   # SNMP client

--help lists every flag. Full CLI reference in glances-rs-docs.

API

The -w server speaks upstream-compatible REST on port 61208: GET /api/4/{plugin} for any plugin, /api/4/all for the full snapshot, per-field history, an SSE event stream, and POST mutators for alerts and extended process stats. HTTP Basic when started with --auth-enabled (or X-API-Key when GLANCES_API_KEY is set); no JWT issuer (POST /api/4/token answers 501). Full route reference with examples: docs/api.md. GET /api/4/health rolls every check into one status for dashboards and scripts. When nobody has asked for data in 30 seconds the server drops to one heartbeat tick per 30 seconds instead of ticking every 2 seconds, and resumes full speed on the next request.

Scope

36 plugins (cpu, mem, load, network, diskio, fs, sensors, gpu, processlist, alert, …), 6 output surfaces. Anything not implemented answers an error — never a silent stub. Owned gaps live in limitations. Linux x86_64 and aarch64: the full tree (lib, bins, tests) typechecks for both (cargo check --target aarch64-unknown-linux-gnu); only x86_64 is runtime-tested.

Constraints

Enforced by lint on every build. No opt-out.

1. No [dependencies] in Cargo.toml — std/core/alloc plus direct libc FFI only.
2. No file longer than 256 lines, comments included.
3. No unsafe outside src/platform/linux/.
4. No shell expansion — explicit argv only.

Documentation

Full docs live in glances-rs-docs: architecture · plugins · outputs · build & test · security · limitations · CLI

License & Credits

LGPL-3.0-only, matching upstream Glances. See LICENSE.

Derivative work of Glances by Nicolas Hennion (Nicolargo) and contributors — the architecture, plugin model, and CLI surface are theirs. Full attribution on the about page.