You could use a pool, if you are fine with the “second” dag run being run later.
> On 17 Jan 2017, at 16:18, Boris Tyukin <bo...@boristyukin.com> wrote: > > hello, > > I would like to prevent a DAG from scheduling / running concurrently > whether by scheduler or if triggered externally (via airflow trigger_dag or > UI). > > I tried to set max_active_runs to 1 but i did not work for externally > triggered case - airflow would still go ahead and execute multiple dag runs. > > I see this is done intentionally in dagrun_exists_dep.py: > > running_dagruns = DagRun.find( > dag_id=dag.dag_id, > state=State.RUNNING, > *external_trigger=False,* > session=session > ) > Is there any other way of forcing only one DAG run at the time? > > I am aware of depends_on_past=True but I use PythonBranch operators and > that setting does not make sense in my case.
