Airflow scheduler can not connect to Kubernetes service api - kubernetes

Question

I am trying to setup airflow with Kubernetes executor and on scheduler container startup it hangs for a while and then I get https timeout error as follows. The ip address in message is correct and inside container I can run curl kubernetes:443 or curl 10.96.0.1:443 or nc -zv 10.96.0.1 443 so I assume there is no firewall or so blocking access.
I am using local kubernetes as well as aws EKS but same error, I can see that ip changes in different clusters.
I have looked at google to find a solution but did not see similar cases.
│ File "/usr/local/lib/python3.6/site-packages/airflow/contrib/executors/kubernetes_executor.py", line 335, in run │
│ self.worker_uuid, self.kube_config) │
│ File "/usr/local/lib/python3.6/site-packages/airflow/contrib/executors/kubernetes_executor.py", line 359, in _run │
│ **kwargs): │
│ File "/usr/local/lib/python3.6/site-packages/kubernetes/watch/watch.py", line 144, in stream │
│ for line in iter_resp_lines(resp): │
│ File "/usr/local/lib/python3.6/site-packages/kubernetes/watch/watch.py", line 48, in iter_resp_lines │
│ for seg in resp.read_chunked(decode_content=False): │
│ File "/usr/local/lib/python3.6/site-packages/urllib3/response.py", line 781, in read_chunked │
│ self._original_response.close() │
│ File "/usr/local/lib/python3.6/contextlib.py", line 99, in __exit__ │
│ self.gen.throw(type, value, traceback) │
│ File "/usr/local/lib/python3.6/site-packages/urllib3/response.py", line 430, in _error_catcher │
│ raise ReadTimeoutError(self._pool, None, "Read timed out.") │
│ urllib3.exceptions.ReadTimeoutError: HTTPSConnectionPool(host='10.96.0.1', port=443): Read timed out.
update: I found my problem, but no solution yet.
https://github.com/kubernetes-client/python/issues/990

Answer 1

There is an option to set the value via the ENV variable. In your charts/airflow.yaml file, you can set the variable as follows and that should solve your problem,
AIRFLOW__KUBERNETES__KUBE_CLIENT_REQUEST_ARGS: {"_request_timeout" : [50, 50]}
PR Reference: https://github.com/apache/airflow/pull/6643
Problem Discussion: https://issues.apache.org/jira/browse/AIRFLOW-6040
airflow.yaml full code
airflow:
image:
repository: airflow-docker-local
tag: 1
executor: Kubernetes
service:
type: LoadBalancer
config:
AIRFLOW__CORE__SQL_ALCHEMY_CONN: postgresql+psycopg2://postgres:airflow#airflow-postgresql:5432/airflow
AIRFLOW__CELERY__RESULT_BACKEND: db+postgresql://postgres:airflow#airflow-postgresql:5432/airflow
AIRFLOW__CELERY__BROKER_URL: redis://:airflow#airflow-redis-master:6379/0
AIRFLOW__CORE__REMOTE_LOGGING: True
AIRFLOW__CORE__REMOTE_LOG_CONN_ID: my_s3_connection
AIRFLOW__CORE__REMOTE_BASE_LOG_FOLDER: s3://xxx-airflow/logs
AIRFLOW__WEBSERVER__LOG_FETCH_TIMEOUT_SEC: 25
AIRFLOW__CORE__LOAD_EXAMPLES: True
AIRFLOW__WEBSERVER__EXPOSE_CONFIG: True
AIRFLOW__CORE__FERNET_KEY: -xyz=
AIRFLOW__KUBERNETES__WORKER_CONTAINER_REPOSITORY: airflow-docker-local
AIRFLOW__KUBERNETES__WORKER_CONTAINER_TAG: 1
AIRFLOW__KUBERNETES__WORKER_CONTAINER_IMAGE_PULL_POLICY: Never
AIRFLOW__KUBERNETES__WORKER_SERVICE_ACCOUNT_NAME: airflow
AIRFLOW__KUBERNETES__DAGS_VOLUME_CLAIM: airflow
AIRFLOW__KUBERNETES__NAMESPACE: airflow
AIRFLOW__KUBERNETES__KUBE_CLIENT_REQUEST_ARGS: {"_request_timeout" : [50, 50]}
persistence:
enabled: true
existingClaim: ''
workers:
enabled: true
postgresql:
enabled: true
redis:
enabled: true