Config Param

Airflow’s behavior is controlled by config params set in airflow.cfg (or equivalent environment variables, AIRFLOW__SECTION__KEY) — one central file rather than per-DAG settings.

Params worth knowing:

• executor — which executor runs tasks (SequentialExecutor, LocalExecutor, CeleryExecutor, …)
• sql_alchemy_conn — the metadata database connection string
• parallelism — max task instances running across the whole Airflow instance
• dags_folder — where the Scheduler looks for DAG files

Environment variables override the file, which is why containerized/cloud Airflow (Docker, MWAA) usually configures it via env vars rather than editing the file directly.

See also: Scheduler