Environment Variables

The indexer, webserver, and ingester components support configuring some parameters via environment variables rather than config files. This helps make more generic configuration files for bigger deployments. Configuration variables that can contain multiple directives are configured in environment variables using a comma separated list. For instance, to specify the ingest secret when launching the Federator:

GRAVWELL_INGEST_SECRET=MyIngestSecret /opt/gravwell/bin/gravwell_federator

Loading Values From Files

If “_FILE” is added to the end of the environment variable name, Gravwell assumes the variable contains the path to a file which in turn contains the desired data. This is particularly useful in combination with Docker’s “secrets” feature.

GRAVWELL_INGEST_AUTH_FILE=/run/secrets/ingest_secret /opt/gravwell/bin/gravwell_indexer

Note

Environment variable values are only used when the corresponding field is not explicitly set in the appropriate config file (gravwell.conf or an ingester’s config file).

Indexer and Webserver

The table below shows which gravwell.conf parameters can be set via environment variables for the indexer and the webserver. Note that these variables are only used if the parameter is not configured in gravwell.conf.

gravwell.conf variable	Environment Variable	Example
Ingest-Auth	GRAVWELL_INGEST_AUTH	GRAVWELL_INGEST_AUTH=CE58DD3F22422C2E348FCE56FABA131A
Control-Auth	GRAVWELL_CONTROL_AUTH	GRAVWELL_CONTROL_AUTH=C2018569D613932A6BBD62A03A101E84
Indexer-UUID	GRAVWELL_INDEXER_UUID	GRAVWELL_INDEXER_UUID=a6bb4386-3433-11e8-bc0b-b7a5a01a3120
Webserver-UUID	GRAVWELL_WEBSERVER_UUID	GRAVWELL_WEBSERVER_UUID=b3191f54-3433-11e8-a0c2-afbff4695836
Remote-Indexers	GRAVWELL_REMOTE_INDEXERS	GRAVWELL_REMOTE_INDEXERS=172.20.0.1:9404,172.20.0.2:9404
Replication-Peers	GRAVWELL_REPLICATION_PEERS	GRAVWELL_REPLICATION_PEERS=172.20.0.1:9406,172.20.0.2:9406
Datastore	GRAVWELL_DATASTORE	GRAVWELL_DATASTORE=172.20.0.10:9405

Ingesters

Ingesters can also accept some parameters as environment variables rather than setting them explicitly in the configuration file.

Config file variable	Environment Variable	Example
Ingest-Secret	GRAVWELL_INGEST_SECRET	GRAVWELL_INGEST_SECRET=CE58DD3F22422C2E348FCE56FABA131A
Log-Level	GRAVWELL_LOG_LEVEL	GRAVWELL_LOG_LEVEL=DEBUG
Cleartext-Backend-target	GRAVWELL_CLEARTEXT_TARGETS	GRAVWELL_CLEARTEXT_TARGETS=172.20.0.1:4023,172.20.0.2:4023
Encrypted-Backend-target	GRAVWELL_ENCRYPTED_TARGETS	GRAVWELL_ENCRYPTED_TARGETS=172.20.0.1:4024,172.20.0.2:4024
Pipe-Backend-target	GRAVWELL_PIPE_TARGETS	GRAVWELL_PIPE_TARGETS=/opt/gravwell/comms/pipe

Federator-specific variables

Because the federator may run many listeners, each with a different ingest secret associated with it, it recognizes a special set of environment variables to configure those listener secrets at runtime.

Each listener has a name. In the example below, the listener is named “base”:

[IngestListener "base"]
	Cleartext-Bind = 0.0.0.0:4023
	Tags=syslog

In order to specify an ingest secret for that listener at runtime, we use the variable FEDERATOR_base_INGEST_SECRET:

FEDERATOR_base_INGEST_SECRET=SuperSecret /opt/gravwell/bin/gravwell_federator

Or we can specify a file as with other environment variables:

FEDERATOR_base_INGEST_SECRET_FILE=/run/secrets/federator_base_secret /opt/gravwell/bin/gravwell_federator

Datastore-specific variables

The Datastore can be configured at run-time by environment variables:

gravwell.conf variable	Environment variable	Example
Datastore-Listen-Address	GRAVWELL_DATASTORE_LISTEN_ADDRESS	GRAVWELL_DATASTORE_LISTEN_ADDRESS=192.168.1.100
Datastore-Port	GRAVWELL_DATASTORE_LISTEN_PORT	GRAVWELL_DATASTORE_LISTEN_PORT=9995