Configuration reference

To configure nohub, use environment variables, or place a .env file in its directory.

The recognized environment variables are described below.

TCP

NOHUB_TCP_HOST

TCP host to listen on. This is where clients can command and send commands. Set to * to listen on all available interfaces, or to 0.0.0.0 to only listen over IPv4.

Defaults to *.

NOHUB_TCP_PORT

TCP port to listen on. This is the port where clients can connect and send commands. Defaults to 9980.

NOHUB_TCP_COMMAND_BUFFER_SIZE

Buffer size for incoming data. Any command larger than this buffer will be dropped. Prevents clients from sending too many or too large commands in one go.

Recognizes simple numbers ( 1024 ), or human-readable sizes ( 100b, 1kb, etc. ).

Games

See also

See Games to learn more.

NOHUB_GAMES

A list of games recognized by nohub. Each game should reside in its own line, each line containing the game’s ID and its name. For example:

q5jMbqNLKQSy0FxhTCHZ9 Forest Brawl
Yf8cBD_EmJa26xRr_2hoX Campfire: Surviving Orom

Defaults to an empty list.

Metrics

NOHUB_METRICS_ENABLED

Set to true to enable metrics.

Defaults to true.

NOHUB_METRICS_HOST

Metrics are served over HTTP. This setting controls which interfaces to listen on for HTTP connections. Set to * to listen on all interfaces, or to 0.0.0.0 to only listen over IPv4.

Defaults to *.

NOHUB_METRICS_PORT

Metrics are served over HTTP. This setting controls which port to listen on for HTTP connections.

Defaults to 9981.

Lobbies

See also

See Lobbies to learn more.

NOHUB_LOBBIES_ID_LENGTH

Length of IDs generated for lobbies.

Defaults to 8.

NOHUB_LOBBIES_WITHOUT_GAME

Set to true to enable lobbies that don’t belong to any game.

Defaults to true.

NOHUB_LOBBIES_MAX_COUNT

Maximum number of active lobbies allowed on this instance.

Set to 0 to disable this limit.

Defaults to 32768.

NOHUB_LOBBIES_MAX_PER_SESSION

Maximum number of active lobbies allowed per session.

Set to 0 to disable this limit.

Defaults to 4.

NOHUB_LOBBIES_MAX_DATA_ENTRIES

Maximum number of custom data entries per lobby.

Note that this does not limit the actual data size of those entries - that is practically limited by how much data fits into a single command, see NOHUB_TCP_COMMAND_BUFFER_SIZE.

Set to 0 to disable this limit.

Defaults to 128.

Sessions

See also

See Sessions to learn more.

NOHUB_SESSIONS_ID_LENGTH

Length of IDs generated for sessions.

Defaults to 12.

NOHUB_SESSIONS_ARBITRARY_GAME_ID

Set to true to enable sessions that reference unknown games. This will enable clients to use any game, not just the ones configured in NOHUB_GAMES.

Defaults to true.

NOHUB_SESSIONS_DEFAULT_GAME_ID

Assign a game to each new session - this effectively means that nohub will allow only a single game.

Use an ID from the list specified in NOHUB_GAMES.

Defaults to an empty string.

NOHUB_SESSIONS_MAX_COUNT

Maximum number of sessions managed by this instance.

Set to 0 to disable this limit.

Defaults to 262144.

NOHUB_SESSIONS_MAX_PER_ADDRESS

Maximum number of sessions from the same IP address ( disregarding port ).

Set to 0 to disable this limit.

Defaults to 64.

Logging

NOHUB_LOG_LEVEL

Logging level.

Known values are silent, trace, debug, info, warn, error, fatal.

Defaults to info.