Configuration Settings

The value of each BigchainDB Server configuration setting is determined according to the following rules:

• If it’s set by an environment variable, then use that value
• Otherwise, if it’s set in a local config file, then use that value
• Otherwise, use the default value

For convenience, here’s a list of all the relevant environment variables (documented below):

BIGCHAINDB_KEYPAIR_PUBLIC
BIGCHAINDB_KEYPAIR_PRIVATE
BIGCHAINDB_KEYRING
BIGCHAINDB_DATABASE_BACKEND
BIGCHAINDB_DATABASE_HOST
BIGCHAINDB_DATABASE_PORT
BIGCHAINDB_DATABASE_NAME
BIGCHAINDB_DATABASE_REPLICASET
BIGCHAINDB_DATABASE_CONNECTION_TIMEOUT
BIGCHAINDB_DATABASE_MAX_TRIES
BIGCHAINDB_SERVER_BIND
BIGCHAINDB_SERVER_LOGLEVEL
BIGCHAINDB_SERVER_WORKERS
BIGCHAINDB_WSSERVER_SCHEME
BIGCHAINDB_WSSERVER_HOST
BIGCHAINDB_WSSERVER_PORT
BIGCHAINDB_CONFIG_PATH
BIGCHAINDB_BACKLOG_REASSIGN_DELAY
BIGCHAINDB_LOG
BIGCHAINDB_LOG_FILE
BIGCHAINDB_LOG_ERROR_FILE
BIGCHAINDB_LOG_LEVEL_CONSOLE
BIGCHAINDB_LOG_LEVEL_LOGFILE
BIGCHAINDB_LOG_DATEFMT_CONSOLE
BIGCHAINDB_LOG_DATEFMT_LOGFILE
BIGCHAINDB_LOG_FMT_CONSOLE
BIGCHAINDB_LOG_FMT_LOGFILE
BIGCHAINDB_LOG_GRANULAR_LEVELS
BIGCHAINDB_DATABASE_SSL
BIGCHAINDB_DATABASE_LOGIN
BIGCHAINDB_DATABASE_PASSWORD
BIGCHAINDB_DATABASE_CA_CERT
BIGCHAINDB_DATABASE_CERTFILE
BIGCHAINDB_DATABASE_KEYFILE
BIGCHAINDB_DATABASE_KEYFILE_PASSPHRASE
BIGCHAINDB_DATABASE_CRLFILE
BIGCHAINDB_GRAPHITE_HOST

The local config file is $HOME/.bigchaindb by default (a file which might not even exist), but you can tell BigchainDB to use a different file by using the -c command-line option, e.g. bigchaindb -c path/to/config_file.json start or using the BIGCHAINDB_CONFIG_PATH environment variable, e.g. BIGHAINDB_CONFIG_PATH=.my_bigchaindb_config bigchaindb start. Note that the -c command line option will always take precedence if both the BIGCHAINDB_CONFIG_PATH and the -c command line option are used.

You can read the current default values in the file bigchaindb/__init__.py. (The link is to the latest version.)

Running bigchaindb -y configure mongodb will generate a local config file in $HOME/.bigchaindb with all the default values (for using MongoDB as the database backend), with two exceptions: it will generate a valid private/public keypair, rather than using the default keypair (None and None).

keypair.public & keypair.private

The cryptographic keypair used by the node. The public key is how the node idenifies itself to the world. The private key is used to generate cryptographic signatures. Anyone with the public key can verify that the signature was generated by whoever had the corresponding private key.

Example using environment variables

export BIGCHAINDB_KEYPAIR_PUBLIC=8wHUvvraRo5yEoJAt66UTZaFq9YZ9tFFwcauKPDtjkGw
export BIGCHAINDB_KEYPAIR_PRIVATE=5C5Cknco7YxBRP9AgB1cbUVTL4FAcooxErLygw1DeG2D

Example config file snippet

"keypair": {
  "public": "8wHUvvraRo5yEoJAt66UTZaFq9YZ9tFFwcauKPDtjkGw",
  "private": "5C5Cknco7YxBRP9AgB1cbUVTL4FAcooxErLygw1DeG2D"
}

Internally (i.e. in the Python code), both keys have a default value of None, but that’s not a valid key. Therefore you can’t rely on the defaults for the keypair. If you want to run BigchainDB, you must provide a valid keypair, either in the environment variables or in the local config file. You can generate a local config file with a valid keypair (and default everything else) using bigchaindb -y configure mongodb.

keyring

A list of the public keys of all the nodes in the cluster, excluding the public key of this node.

Example using an environment variable

export BIGCHAINDB_KEYRING=BnCsre9MPBeQK8QZBFznU2dJJ2GwtvnSMdemCmod2XPB:4cYQHoQrvPiut3Sjs8fVR1BMZZpJjMTC4bsMTt9V71aQ

Note how the keys in the list are separated by colons.

Example config file snippet

"keyring": ["BnCsre9MPBeQK8QZBFznU2dJJ2GwtvnSMdemCmod2XPB",
            "4cYQHoQrvPiut3Sjs8fVR1BMZZpJjMTC4bsMTt9V71aQ"]

Default value (from a config file)

"keyring": []

database.*

The settings with names of the form database.* are for the database backend (currently either MongoDB or RethinkDB). They are:

• database.backend is either mongodb or rethinkdb.
• database.host is the hostname (FQDN) of the backend database.
• database.port is self-explanatory.
• database.name is a user-chosen name for the database inside MongoDB or RethinkDB, e.g. bigchain.
• database.replicaset is only relevant if using MongoDB; it’s the name of the MongoDB replica set, e.g. bigchain-rs.
• database.connection_timeout is the maximum number of milliseconds that BigchainDB will wait before giving up on one attempt to connect to the database backend.
• database.max_tries is the maximum number of times that BigchainDB will try to establish a connection with the database backend. If 0, then it will try forever.
• database.ssl is a flag that determines if BigchainDB connects to the backend database over TLS/SSL or not. This can be set to either true or false (the default). Note: This parameter is only supported for the MongoDB backend currently.
• database.login and database.password are the login and password used to authenticate to the database before performing any operations, specified in plaintext. The default values for both are currently null, which means that BigchainDB will not authenticate with the backend database. Note: These parameters are only supported for the MongoDB backend currently.
• database.ca_cert, database.certfile, database.keyfile and database.crlfile are the paths to the CA, signed certificate, private key and certificate revocation list files respectively. Note: These parameters are only supported for the MongoDB backend currently.
• database.keyfile_passphrase is the private key decryption passphrase, specified in plaintext. Note: This parameter is only supported for the MongoDB backend currently.

Example using environment variables

export BIGCHAINDB_DATABASE_BACKEND=mongodb
export BIGCHAINDB_DATABASE_HOST=localhost
export BIGCHAINDB_DATABASE_PORT=27017
export BIGCHAINDB_DATABASE_NAME=bigchain
export BIGCHAINDB_DATABASE_REPLICASET=bigchain-rs
export BIGCHAINDB_DATABASE_CONNECTION_TIMEOUT=5000
export BIGCHAINDB_DATABASE_MAX_TRIES=3

Default values

If (no environment variables were set and there’s no local config file), or you used bigchaindb -y configure rethinkdb to create a default local config file for a RethinkDB backend, then the defaults will be:

"database": {
    "backend": "rethinkdb",
    "host": "localhost",
    "port": 28015,
    "name": "bigchain",
    "connection_timeout": 5000,
    "max_tries": 3
}

If you used bigchaindb -y configure mongodb to create a default local config file for a MongoDB backend, then the defaults will be:

"database": {
    "backend": "mongodb",
    "host": "localhost",
    "port": 27017,
    "name": "bigchain",
    "replicaset": "bigchain-rs",
    "connection_timeout": 5000,
    "max_tries": 3,
    "login": null,
    "password": null
    "ssl": false,
    "ca_cert": null,
    "crlfile": null,
    "certfile": null,
    "keyfile": null,
    "keyfile_passphrase": null,
}

server.bind, server.loglevel & server.workers

These settings are for the Gunicorn HTTP server, which is used to serve the HTTP client-server API.

server.bind is where to bind the Gunicorn HTTP server socket. It’s a string. It can be any valid value for Gunicorn’s bind setting. If you want to allow IPv4 connections from anyone, on port 9984, use 0.0.0.0:9984. In a production setting, we recommend you use Gunicorn behind a reverse proxy server. If Gunicorn and the reverse proxy are running on the same machine, then use localhost:PORT where PORT is not 9984 (because the reverse proxy needs to listen on port 9984). Maybe use PORT=9983 in that case because we know 9983 isn’t used. If Gunicorn and the reverse proxy are running on different machines, then use A.B.C.D:9984 where A.B.C.D is the IP address of the reverse proxy. There’s more information about deploying behind a reverse proxy in the Gunicorn documentation. (They call it a proxy.)

server.loglevel sets the log level of Gunicorn’s Error log outputs. See Gunicorn’s documentation for more information.

server.workers is the number of worker processes for handling requests. If None (the default), the value will be (2 × cpu_count + 1). Each worker process has a single thread. The HTTP server will be able to handle server.workers requests simultaneously.

Example using environment variables

export BIGCHAINDB_SERVER_BIND=0.0.0.0:9984
export BIGCHAINDB_SERVER_LOGLEVEL=debug
export BIGCHAINDB_SERVER_WORKERS=5

Example config file snippet

"server": {
    "bind": "0.0.0.0:9984",
    "loglevel": "debug",
    "workers": 5,
}

Default values (from a config file)

"server": {
    "bind": "localhost:9984",
    "loglevel": "info",
    "workers": null,
}

wsserver.scheme, wsserver.host and wsserver.port

These settings are for the aiohttp server, which is used to serve the WebSocket Event Stream API. wsserver.scheme should be either "ws" or "wss" (but setting it to "wss" does not enable SSL/TLS). wsserver.host is where to bind the aiohttp server socket and wsserver.port is the corresponding port. If you want to allow connections from anyone, on port 9985, set wsserver.host to 0.0.0.0 and wsserver.port to 9985.

Example using environment variables

export BIGCHAINDB_WSSERVER_SCHEME=ws
export BIGCHAINDB_WSSERVER_HOST=0.0.0.0
export BIGCHAINDB_WSSERVER_PORT=9985

Example config file snippet

"wsserver": {
    "scheme": "wss",
    "host": "0.0.0.0",
    "port": 65000
}

Default values (from a config file)

"wsserver": {
    "scheme": "ws",
    "host": "localhost",
    "port": 9985
}

backlog_reassign_delay

Specifies how long, in seconds, transactions can remain in the backlog before being reassigned. Long-waiting transactions must be reassigned because the assigned node may no longer be responsive. The default duration is 120 seconds.

Example using environment variables

export BIGCHAINDB_BACKLOG_REASSIGN_DELAY=30

Default value (from a config file)

"backlog_reassign_delay": 120

log

The log key is expected to point to a mapping (set of key/value pairs) holding the logging configuration.

Example:

{
    "log": {
        "file": "/var/log/bigchaindb.log",
        "error_file": "/var/log/bigchaindb-errors.log",
        "level_console": "info",
        "level_logfile": "info",
        "datefmt_console": "%Y-%m-%d %H:%M:%S",
        "datefmt_logfile": "%Y-%m-%d %H:%M:%S",
        "fmt_console": "%(asctime)s [%(levelname)s] (%(name)s) %(message)s",
        "fmt_logfile": "%(asctime)s [%(levelname)s] (%(name)s) %(message)s",
        "granular_levels": {
            "bichaindb.backend": "info",
            "bichaindb.core": "info"
        }
}

Defaults to:

{
    "log": {
        "file": "~/bigchaindb.log",
        "error_file": "~/bigchaindb-errors.log",
        "level_console": "info",
        "level_logfile": "info",
        "datefmt_console": "%Y-%m-%d %H:%M:%S",
        "datefmt_logfile": "%Y-%m-%d %H:%M:%S",
        "fmt_logfile": "[%(asctime)s] [%(levelname)s] (%(name)s) %(message)s (%(processName)-10s - pid: %(process)d)",
        "fmt_console": "[%(asctime)s] [%(levelname)s] (%(name)s) %(message)s (%(processName)-10s - pid: %(process)d)",
        "granular_levels": {}
}

The next subsections explain each field of the log configuration.

log.file & log.error_file

The full paths to the files where logs and error logs should be written to.

Example:

{
    "log": {
        "file": "/var/log/bigchaindb/bigchaindb.log"
        "error_file": "/var/log/bigchaindb/bigchaindb-errors.log"
    }
}

Defaults to:

* `"~/bigchaindb.log"`
* `"~/bigchaindb-errors.log"`

Please note that the user running bigchaindb must have write access to the locations.

Log rotation

Log files have a size limit of 200 MB and will be rotated up to five times.

For example if we consider the log file setting:

{
    "log": {
        "file": "~/bigchain.log"
    }
}

logs would always be written to bigchain.log. Each time the file bigchain.log reaches 200 MB it would be closed and renamed bigchain.log.1. If bigchain.log.1 and bigchain.log.2 already exist they would be renamed bigchain.log.2 and bigchain.log.3. This pattern would be applied up to bigchain.log.5 after which bigchain.log.5 would be overwritten by bigchain.log.4, thus ending the rotation cycle of whatever logs were in bigchain.log.5.

log.level_console

The log level used to log to the console. Possible allowed values are the ones defined by Python, but case insensitive for convenience’s sake:

"critical", "error", "warning", "info", "debug", "notset"

Example:

{
    "log": {
        "level_console": "info"
    }
}

Defaults to: "info".

log.level_logfile

The log level used to log to the log file. Possible allowed values are the ones defined by Python, but case insensitive for convenience’s sake:

"critical", "error", "warning", "info", "debug", "notset"

Example:

{
    "log": {
        "level_file": "info"
    }
}

Defaults to: "info".

log.datefmt_console

The format string for the date/time portion of a message, when logged to the console.

Example:

{
    "log": {
        "datefmt_console": "%x %X %Z"
    }
}

Defaults to: "%Y-%m-%d %H:%M:%S".

For more information on how to construct the format string please consult the table under Python’s documentation of time.strftime(format[, t])

log.datefmt_logfile

The format string for the date/time portion of a message, when logged to a log file.

Example:

{
    "log": {
        "datefmt_logfile": "%c %z"
    }
}

Defaults to: "%Y-%m-%d %H:%M:%S".

For more information on how to construct the format string please consult the table under Python’s documentation of time.strftime(format[, t])

log.fmt_console

A string used to format the log messages when logged to the console.

Example:

{
    "log": {
        "fmt_console": "%(asctime)s [%(levelname)s] %(message)s %(process)d"
    }
}

Defaults to: "[%(asctime)s] [%(levelname)s] (%(name)s) %(message)s (%(processName)-10s - pid: %(process)d)"

For more information on possible formatting options please consult Python’s documentation on LogRecord attributes

log.fmt_logfile

A string used to format the log messages when logged to a log file.

Example:

{
    "log": {
        "fmt_logfile": "%(asctime)s [%(levelname)s] %(message)s %(process)d"
    }
}

Defaults to: "[%(asctime)s] [%(levelname)s] (%(name)s) %(message)s (%(processName)-10s - pid: %(process)d)"

For more information on possible formatting options please consult Python’s documentation on LogRecord attributes

log.granular_levels

Log levels for BigchainDB’s modules. This can be useful to control the log level of specific parts of the application. As an example, if you wanted the logging of the core.py module to be more verbose, you would set the configuration shown in the example below.

Example:

{
    "log": {
        "granular_levels": {
            "bichaindb.core": "debug"
        }
}

Defaults to: "{}"

graphite.host

The host name or IP address of a server listening for statsd events on UDP port 8125. This defaults to localhost, and if no statsd collector is running, the events are simply dropped by the operating system.

Example using environment variables

export BIGCHAINDB_GRAPHITE_HOST=10.0.0.5

Example config file snippet

"graphite": {
    "host": "10.0.0.5"
}

Default values (from a config file)

"graphite": {
    "host": "localhost"
}