🎮 CS2 Server Maintainer

An automated management and maintenance utility for Counter-Strike 2 dedicated servers. Designed to keep your CS2 server updated, healthy, and running smoothly without manual intervention.

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🚧 Status: Beta version

Note: This project is actively under development. Features, setup procedures, and configurations are subject to rapid change. Please report bugs at issues.

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✨ Features & Capabilities

• 🔄 Auto-Updates: Detects new CS2 builds in three ways: a fresh "Counter-Strike 2 Update" post on Steam news, the server's own "restart required" notice, and regular SteamCMD checks. Announced updates install as soon as SteamCMD has the build. Otherwise updates wait for an empty server, your restart window, or a maximum wait. Players get an in-game countdown first.
• 🔁 Auto-Restarts: Crash recovery with exponential backoff, plus an optional daily restart.
• 📊 Health Monitoring: A2S queries catch a hung server, not just a dead one. Bots don't count as players.
• 🧩 Keeps Metamod loaded: CS2 updates replace gameinfo.gi and drop lines like Game csgo/addons/metamod. Before every start, the maintainer re-adds the search paths you list.
• 🚨 Admin Alerts: A Discord webhook tells admins when the maintainer fails, the server crashes or restarts, and when an update is announced, installed or fails.
• 🤖 Discord Admin Bot (optional): /restart, /stop, /checkupdate and /health slash commands, limited to one role.
• 🧱 Safe by default: Clean shutdown (SIGINT on Linux, RCON quit on Windows). The server can't outlive the maintainer. A lock stops a second maintainer from running. State is written atomically and logs rotate.
• 🛠 Configurable Hooks (planned): Run custom scripts before and after an update.

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🤖 Preview

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🛠 Prerequisites

Before installing, ensure you have the following installed on your host system:

• Operating System: Linux (Ubuntu 20.04+ / Debian recommended) or Windows Server
• SteamCMD installed and configured

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🚀 Quick Start

Download: grab cs2-maintainer-<version>-windows-amd64.zip or -linux-amd64.tar.gz from Releases. Each one holds the program and config.example.json; rename that to config.json and edit it. Builds of every commit are under Actions: open a run, then Artifacts.

To publish a release, push a version tag. The workflow tests, builds, and creates the release with both packages:

git tag v1.0.0
git push origin v1.0.0

Build it yourself: requires Go 1.22+. The result is a single binary; the only library it uses is discordgo, for the optional bot.

Windows (PowerShell):

cd maintainer
copy config.example.json config.json    # then edit paths, args, rcon_password, gslt
go build -o cs2-maintainer.exe .
.\cs2-maintainer.exe -validate          # checks the config and prints the launch command
.\cs2-maintainer.exe -check-update      # installed vs. latest build, without touching anything
.\cs2-maintainer.exe                    # run it

Linux:

cd maintainer
cp config.example.json config.json      # then edit paths, args, rcon_password, gslt
go build -o cs2-maintainer .
./cs2-maintainer -validate
./cs2-maintainer -check-update
./cs2-maintainer

On Windows, the name after -o is used exactly as written, so keep the .exe. Plain go build (no -o) also works and names the file cs2-maintainer.exe or cs2-maintainer for you.

If install_dir has no CS2 install yet, the first run installs it with SteamCMD.

Cross-compile, for example to build the Linux binary on Windows:

# PowerShell
$env:GOOS="linux";   $env:GOARCH="amd64"; go build -o dist/cs2-maintainer .
$env:GOOS="windows"; $env:GOARCH="amd64"; go build -o dist/cs2-maintainer.exe .
Remove-Item Env:GOOS, Env:GOARCH         # back to building for this PC

# bash
GOOS=linux   GOARCH=amd64 go build -o dist/cs2-maintainer .
GOOS=windows GOARCH=amd64 go build -o dist/cs2-maintainer.exe .

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⚙️ Configuration

See maintainer/config.example.json for every option, its default, and a comment explaining it. Config files may contain // and /* */ comments. Only install_dir and steamcmd_path are required. Durations are strings such as "15s" or "10m". Relative paths resolve against the config file's folder. Unknown keys are rejected, so typos fail loudly.

Key	What it does
server.args	Extra launch args (map, game mode, ...). -dedicated, -port, -usercon, the RCON password and the GSLT are added for you.
server.rcon_password	Used for clean shutdown on Windows and for countdown messages. Strongly recommended.
server.console_window	Windows: the server gets its own console window, like a .bat (default). You see its output and can type commands there. Set to false to capture its output into logs/server.log instead.
update.window	Daily window (start/end, local time, may cross midnight) when updates install even with players online.
update.max_defer	Longest an update waits for an empty server. After an update, outdated servers reject updated clients, so don't wait forever. "0s" = no limit.
update.validate	Validate all files on every update. Off by default because validation is slow; it always runs after a failed update.
restart.daily_at	Optional daily restart time, for example "05:00".
discord_webhook	Discord webhook for admin alerts: maintainer failures, server restarts, updates.
discord_bot_token / server_manager_role_id	Optional admin bot (see below). Both are needed to turn it on.
gameinfo_search_paths	Search paths to keep in game/csgo/gameinfo.gi, for example ["csgo/addons/metamod"]. Each is re-added as a Game line after Game_LowViolence before every server start, since updates reset the file.
news.title / news.max_age	A Steam news post whose title contains title (default "Counter-Strike 2 Update") and that is newer than max_age (default 6h) triggers an update.

Secrets can come from the environment instead: CS2M_RCON_PASSWORD, CS2M_GSLT, CS2M_DISCORD_WEBHOOK.

Logs go to logs/maintainer.log (the tool) and logs/server.log (CS2 console). Both rotate.

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🤖 Discord Admin Bot (optional)

Command	What it does
/health	Status (online, starting, not responding, restarting, stopped), map, players, uptime, build, pending update
/restart	Restarts the server with the in-game countdown, or starts it after /stop. Installs a pending update in the same restart.
/stop	Stops the server. It stays down, even if the maintainer restarts, until someone runs /restart.
/checkupdate	Asks Steam for a new CS2 build right now

Only members with the configured role can use the commands; everyone else gets a private "you need the role" reply. Every use is logged and posted to discord_webhook with the user's name.

Setup

1. Go to the Discord Developer Portal, click New Application, open Bot, click Reset Token, and copy the token into discord_bot_token. You can use the CS2M_DISCORD_BOT_TOKEN environment variable instead.
2. Open OAuth2 > URL Generator, tick bot and applications.commands, open the URL, and invite the bot to your server. No permissions or privileged intents are needed.
3. In Discord, turn on Settings > Advanced > Developer Mode, then right-click your admin role in Server Settings > Roles > Copy Role ID and put it in server_manager_role_id.
4. Restart the maintainer. The log shows discord bot ready. The commands can take a minute to appear the first time.

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📦 Deployment

Linux (systemd): copy maintainer/deploy/cs2-maintainer.service to /etc/systemd/system/, adjust User and paths, then run systemctl enable --now cs2-maintainer. The tool also copies steamclient.so into ~/.steam/sdk64/ for you, which is the most common reason a Linux CS2 server fails to start.

Windows: run it as a service with NSSM:

nssm install CS2Maintainer C:\cs2-maintainer\cs2-maintainer.exe -config C:\cs2-maintainer\config.json
nssm set CS2Maintainer AppDirectory C:\cs2-maintainer
nssm start CS2Maintainer

Set server.rcon_password, otherwise Windows can only force-kill the server. Add an antivirus exclusion for the CS2 and SteamCMD folders.

Firewall: open the game port (default 27015) for UDP. RCON shares the port over TCP, so only open TCP if you need RCON from outside.

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🧪 Development

maintainer/
├── main.go     flags and wiring
├── core/       all logic (controller, supervisor, updater, health, rcon, news, ...)
├── tests/      test suite
└── deploy/     systemd unit

cd maintainer
go test ./...              # or: go test ./tests/ -v

The tests include fake A2S and RCON servers, a fake Steam news API and Discord webhook, and the controller's policies (crash backoff, hang detection, update deferral, news-triggered updates). One test launches the test binary itself as a stand-in CS2 server to exercise the real start, health and stop path.

See maintainer/plan.md for the design and the reasoning behind it.