Environment Variables

Configuring Arweave with AR_* environment variables

Environment Variables

AR_* configuration variables are only available from Arweave 2.9.6 onward.

Every configuration option can be set through an environment variable.

1. The AR_* Naming Convention

The variable name is derived from the option's dotted key: prefix AR_, upper-case each segment, and join the segments with underscores.

Option key	Environment variable
port	AR_PORT
data_dir	AR_DATA_DIR
mining.enabled	AR_MINING_ENABLED
mining.address	AR_MINING_ADDRESS
sync.jobs	AR_SYNC_JOBS
network.server.tcp.max_connections	AR_NETWORK_SERVER_TCP_MAX_CONNECTIONS

Values are written the same way as on the command line:

AR_DATA_DIR=/opt/data \
AR_MINING_ENABLED=true \
AR_MINING_ADDRESS=En2eqsVJARnTVOSh723PBXAKGmKgrGSjQ2YIGwE_ZRI \
./bin/start

Use ./bin/arweave config help <group> to look up an option's dotted key - the environment variable name follows mechanically from it. AR_* variables that do not match a known option key are ignored, so double-check the spelling when a setting doesn't seem to take effect.

Environment variables set scalar values: booleans, numbers, strings, and single peers (AR_PEERS_TRUSTED=188.166.200.45:1984 becomes a one-element list). A value that starts with [ or { is parsed as JSON, so lists and structured options can also be set this way - wrap the value in single quotes so the shell passes it through intact:

AR_PEERS_TRUSTED='["peers.arweave.xyz", "188.166.200.45:1984"]' ./bin/start

For anything beyond a couple of entries, a configuration file may be easier to read and maintain.

2. AR_CONFIG_FILE

AR_CONFIG_FILE points the node at a JSON or YAML configuration file, exactly like the --config_file flag:

AR_CONFIG_FILE=/opt/arweave/config.yaml ./bin/start

Only one config file can be given per launch - setting both AR_CONFIG_FILE and --config_file is an error.

3. Precedence and the Configuration Style

Environment variables sit in the middle of the precedence order: they override values from the config file and are overridden by command-line flags.

4. ARNODE and ARCOOKIE

Two additional variables configure the Erlang VM itself rather than Arweave options: ARNODE sets the Erlang node name and ARCOOKIE the Erlang cookie. You'll need them when running multiple nodes on one server, and commands that talk to a running node - such as config get / config set - must be invoked with the same ARNODE / ARCOOKIE values the node was launched with.