Skip to main content

Global environment variables

This document is a reference for all environment variables on Astronomer with different default values than open source Apache Airflow. You can override default Runtime environment variables, but you can't override system environment variables.

For information on setting your own environment variables, see Environment variables.

System environment variables

On Astro, certain environment variables have preset values that are required and should not be overridden by your team. The following table provides information about each global environment variable set by Astronomer.


The Astro UI does not currently prevent you from setting these environment variables, but attempting to set them can result in unexpected behavior that can include access problems, missing task logs, and failed tasks.

If you need to set one of these variables for a particular use case, contact Astronomer support.

Environment VariableDescriptionValue
AIRFLOW__CELERY_BROKER_TRANSPORT_OPTIONS__SOCKET_TIMEOUTThe amount of time that the Celery executor waits for a response from the Celery backend before throwing an error.30
AIRFLOW__CELERY_BROKER_TRANSPORT_OPTIONS__SOCKET_CONNECT_TIMEOUTThe amount of time that the Celery executor will attempt to connect to the Celery backend before retrying.5
AIRFLOW__CELERY_BROKER_TRANSPORT_OPTIONS__SOCKET_KEEPALIVEWhether the Celery executor will check whether the connection to the Celery backend is still alive.True
AIRFLOW__CELERY_BROKER_TRANSPORT_OPTIONS__RETRY_ON_TIMEOUTWhether the Celery executor will retry a connection to the Celery backend when the connection fails.True
AIRFLOW__LOGGING__DAG_PROCESSOR_LOG_TARGETRoutes scheduler logs to stdoutstdout
AIRFLOW__LOGGING__REMOTE_LOGGINGEnables remote loggingTrue
AIRFLOW__LOGGING__REMOTE_BASE_LOG_FOLDERLocation of remote logging storagebaseLogFolder
AIRFLOW__LOGGING__REMOTE_LOG_CONN_IDID of the connection that provides access to your remote logging location<connection-name>
AIRFLOW__LOGGING__LOGGING_CONFIG_CLASSClass name that specifies the logging configurationastronomer.runtime.logging.logging_config
AIRFLOW_CONN_ASTRO_S3_LOGGINGConnection URI for writing task logs to Astro's managed S3 bucket<Connection-URI>
AIRFLOW__LOGGING__ENCRYPT_S3_LOGSDetermines whether to use server-side encryption for S3 logsFalse
AIRFLOW__WEBSERVER__BASE_URLThe base URL of the Airflow UIhttps://${fullIngressHostname}
AIRFLOW__CORE__SQL_ALCHEMY_CONNThe SqlAlchemy connection string for the metadata databasedbConnSecret
AIRFLOW__WEBSERVER__UPDATE_FAB_PERMSDetermines whether to update FAB permissions on webserver startupTrue
AIRFLOW__WEBSERVER__ENABLE_PROXY_FIXDetermines whether to enable werkzeug ProxyFix middleware for reverse proxyTrue
AIRFLOW_CONN_AIRFLOW_DBThe connection ID for accessing the Airflow metadata databasedbConnSecret
AIRFLOW__CORE__FERNET_KEYThe secret key for saving connection passwords in the metadata databasefernetKeySecret
AIRFLOW__CORE__EXECUTORThe executor class that Airflow uses. Astro supports the Celery and Kubernetes executor.executor
AIRFLOW_HOMEThe home directory for an Astro projectusr/local/airflow
AIRFLOW__KUBERNETES__NAMESPACEThe Kubernetes namespace where Airflow workers are creatednamespace
AIRFLOW__CORE__HOSTNAME_CALLABLEPath to a callable, which resolves to the
AIRFLOW__SCHEDULER__STATSD_ONDetermines whether Statsd is onTrue
AIRFLOW__SCHEDULER__STATSD_HOSTThe hostname for Statsdstatsd.Hostname
AIRFLOW__SCHEDULER__STATSD_PORTThe port for Statsd<statsd-port>
AIRFLOW__METRICS__STATSD_ONDetermines whether metrics are sent to StatsdTrue
AIRFLOW__METRICS__STATSD_HOSTThe hostname for sending metrics to Statsdstatsd.Hostname
AIRFLOW__METRICS__STATSD_PORTThe port for sending metrics to Statsd<statsd-metrics-port>
AIRFLOW__METRICS__STATSD_PREFIXThe prefix for sending the metrics to Statsdairflow
AIRFLOW__WEBSERVER__COOKIE_SECURESets a secure flag on server cookiesTrue
AIRFLOW__WEBSERVER__INSTANCE_NAMEShows the name of your Deployment in the Home view of the Airflow UI<Deployment-Name>
AIRFLOW__CELERY__WORKER_CONCURRENCYDetermines how many tasks each Celery worker can run at any given time and is the basis of worker auto-scaling logic<Max-Tasks-Per-Worker>
AIRFLOW__WEBSERVER__NAVBAR_COLOR(Only Astro Runtime version 9.4.0 and older) The color of the main navigation bar in the Airflow UI#4a4466
AIRFLOW__WEBSERVER__EXPOSE_CONFIGExposes the Configuration tab of the Airflow UI and hides sensitive valuesNON-SENSITIVE-ONLY
AWS_DEFAULT_REGION(AWS clusters only) The region where your cluster is located.The region where you configured your cluster.
AWS_SECRET_ACCESS_KEYThe key secret for accessing Astro's managed S3 bucket¹<s3-aws-access-key-secret>
INSTANCE_TYPEProvides the instance size of the node the DAG is scheduled on.(v1:metadata.labels[''])
OPENLINEAGE_URLThe URL for your Astro lineage backend. The destination for lineage metadata sent from external systems to the OpenLineage API.https://astro-<your-astro-base-domain>
OPENLINEAGE_API_KEYYour OpenLineage API key<your-lineage-api-key>

Was this page helpful?

Sign up for Developer Updates

Get a summary of new Astro features once a month.

You can unsubscribe at any time.
By proceeding you agree to our Privacy Policy, our Website Terms and to receive emails from Astronomer.