Environment Variables

Complete reference for 3x-ui's XUI_* environment variables — database, panel, logging, memory, and the tunnel health monitor.

3x-ui reads its runtime configuration from XUI_* environment variables. On a script install the installer writes them to the service environment file (/etc/default/x-ui, or /etc/conf.d/x-ui / /etc/sysconfig/x-ui depending on the distro); for Docker you set them in docker-compose.yml or docker run -e. Defaults are sensible — set only what you need to change, then restart: systemctl restart x-ui.

Database

Variable	Default	Description
`XUI_DB_TYPE`	`sqlite`	Backend: `sqlite`, or `postgres` (also accepts `postgresql` / `pg`).
`XUI_DB_FOLDER`	`/etc/x-ui`	Folder for the SQLite database file (`x-ui.db`).
`XUI_DB_DSN`	—	PostgreSQL connection string (used when `XUI_DB_TYPE=postgres`).
`XUI_DB_MAX_OPEN_CONNS`	—	Max open connections in the PostgreSQL pool.
`XUI_DB_MAX_IDLE_CONNS`	—	Max idle connections in the PostgreSQL pool.

The default SQLite database path is /etc/x-ui/x-ui.db. See Database for the SQLite ↔ PostgreSQL details.

Panel

Variable	Default	Description
`XUI_PORT`	—	Override the panel port (1–65535). Takes precedence over the stored setting.
`XUI_INIT_WEB_BASE_PATH`	`/`	Initial web base path on first launch (e.g. `/panel`).
`XUI_ENABLE_FAIL2BAN`	`true`	Enable Fail2ban-based IP-limit enforcement.
`XUI_SKIP_HSTS`	`false`	Skip the HSTS header — set `true` when TLS is terminated by a reverse proxy.

Logging & binaries

Variable	Default	Description
`XUI_LOG_LEVEL`	`info`	`debug`, `info`, `notice`, `warning`, or `error`.
`XUI_DEBUG`	`false`	Debug mode (forces log level to `debug`).
`XUI_LOG_FOLDER`	`/var/log/x-ui`	Log output directory.
`XUI_BIN_FOLDER`	`bin`	Folder for the Xray-core binary and geosite/geoip files.

Memory & profiling

The panel keeps memory low via GOGC and periodic releases. These are advanced knobs — leave them unset unless you're tuning a constrained host.

Variable	Default	Description
`XUI_GOGC`	—	Go GC target percentage; lower = less RAM, slightly more CPU.
`XUI_MEMORY_RELEASE_INTERVAL`	—	Minutes between `FreeOSMemory` calls; `0` disables.
`XUI_MEMORY_LIMIT`	—	Go soft memory limit in MiB.
`GOMEMLIMIT`	—	Go-syntax soft limit (e.g. `400MiB`); takes precedence over above.
`XUI_PPROF`	`false`	Expose pprof profiling on `127.0.0.1:6060`.

Xray

Variable	Default	Description
`XRAY_VMESS_AEAD_FORCED`	`false`	Force VMess AEAD.

Tunnel health monitor

Optional watchdog: it probes a URL (optionally through a local Xray inbound) and restarts Xray after repeated failures. A restart drops all connected clients, so enable it deliberately.

Variable	Default	Description
`XUI_TUNNEL_HEALTH_MONITOR`	`false`	Enable the monitor.
`XUI_TUNNEL_HEALTH_PROXY`	—	Proxy to send the probe through, e.g. `socks5://127.0.0.1:1080`. Empty = only checks host connectivity.
`XUI_TUNNEL_HEALTH_URL`	`https://www.cloudflare.com/cdn-cgi/trace`	URL to probe.
`XUI_TUNNEL_HEALTH_INTERVAL`	`30s`	Interval between probes.
`XUI_TUNNEL_HEALTH_TIMEOUT`	`10s`	Per-probe timeout.
`XUI_TUNNEL_HEALTH_FAILURES`	`3`	Consecutive failures before a restart.
`XUI_TUNNEL_HEALTH_COOLDOWN`	`5m`	Minimum delay between restarts.

Unattended install

Variable	Description
`XUI_NONINTERACTIVE`	Set to `1` (or run with no TTY) to install with zero prompts; generated credentials are written to `/etc/x-ui/install-result.env`. See Installation.