Configuration

Configuration overview

简体中文 | English | Wiki home

This page tells you where each kind of setting lives and how to make a change take effect. Paths assume the default installation directory /opt/LLMOJ; if you installed elsewhere with --prefix, use your own directory everywhere.

Where settings live

Page	What it covers
Installation	The installer and its options
Backend configuration	config/backend.yaml: accounts, security, database, mail, storage, contests and display
Registration approval	The registration mode set in Site management, its default in backend.yaml, and reviewers
Two-factor sign-in	Authenticator codes and passkeys, which users set up themselves, and the two-factor.key file
Judge configuration	config/judge.yaml, resizing for more or fewer CPUs, services and checks
AI	AI models, web search, permissions and jobs, set by each user in the site
AI environment	AI directories, keys and environment variables on the server
Environment variables	Environment variables for running, installing and building, and maintenance script options
Frontend configuration	Building the frontend and optional CDN settings
Operations	Nginx, MariaDB, Redis, MinIO, systemd, and changes after installation

Defaults, examples and your own values

• Built-in defaults are what the code uses when a setting is missing. Most settings in backend.yaml and judge.yaml have no built-in default, so deleting a line doesn't bring back the value from an example.
• Examples in the repository (*.example) may contain values meant for another site.
• Installer values are calculated during the first installation from the directory, ports, CPUs and memory. Running the installer again keeps the existing files.
• What's actually in effect is your configuration files together with the systemd units and their drop-in files. The registration mode saved in Site management overrides the one in backend.yaml, and AI settings are stored per user.

Making a change take effect

What you changed	What to do
config/backend.yaml	Check that the YAML is valid, restart libreoj-backend and refresh the browser. A registration mode saved in Site management still takes precedence.
Registration mode in Site management	Nothing: it applies as soon as it's saved. See Registration approval.
config/judge.yaml	Follow Judge configuration: let running judging finish first. Changes to slots, CPUs or directories also need new systemd units.
systemd environment, resource limits or drop-ins	Run systemctl daemon-reload, then restart the service. daemon-reload alone doesn't restart anything.
config/nginx.conf	Check it with nginx -t, then reload Nginx. Keep the domain and the storage download address consistent.
MariaDB, Redis or MinIO	Restart the service at a quiet time and check that the backend can still use it.
Frontend build settings or static files	Rebuild, copy the result to the directory Nginx serves, and refresh the browser.
AI models, search and permissions	Save them in the site. Running jobs check permissions again as they go; see AI.

The installer's options are for the first installation only. Running the installer again with a different --judge-slots, --port or --public-url doesn't reconfigure the site: it may refuse the new values, and it keeps the existing YAML files. Don't delete the installation state, secrets.json, the AI master key or data to get round this.

Common changes

• More or fewer CPUs or memory: resize the judge.
• Site name, ports, domain, mail, upload limits or service memory: Operations.
• AI models, Tavily or MCP: AI.

Back up the database, file storage, configuration and AI keys together: the source code alone can't restore a site. Never put real passwords or keys in the wiki or on GitHub.