The scheduler does not appear to be running. Last heartbeat was received 15 minutes ago. The DAGs list may not update, and new tasks will not be scheduled.

[assadali007]

i am reading book data pipeline with apache airflow i run this example on apache airflow the second task get_pictures python it running for past days and it stucks i don't know what to do
i am learning apache airflow log show of get_pictures look like this anyone know what i need to do,it create the folder of image but image does not download but when i just run get_pictures function on local machine it work fine and also download picture and when i run on dag it stuck when it appear on get_pictures task it happening for past day until now
`import json
import pathlib

import airflow.utils.dates
import requests
import requests.exceptions as requests_exceptions
from airflow import DAG
from airflow.operators.bash import BashOperator
from airflow.operators.python import PythonOperator

dag = DAG(
dag_id="download_rocket_launches",
description="Download rocket pictures of recently launched rockets.",
start_date=airflow.utils.dates.days_ago(1),
schedule_interval=None,
)

download_launches = BashOperator(
task_id="download_launches",
bash_command="curl -o /Users/asadali/airflow/launches.json -L 'https://ll.thespacedevs.com/2.0.0/launch/upcoming'", # noqa: E501
dag=dag,
)

def _get_pictures():
# Ensure directory exists
pathlib.Path("/Users/asadali/airflow/images").mkdir(parents=True, exist_ok=True)

# Download all pictures in launches.json
with open("/Users/asadali/airflow/launches.json") as f:
    launches = json.load(f)
    image_urls = [launch["image"] for launch in launches["results"]]
    for image_url in image_urls:
        try:
            response = requests.get(image_url)
            image_filename = image_url.split("/")[-1]
            target_file = f"/Users/asadali/airflow/images/{image_filename}"
            with open(target_file, "wb") as f:
                f.write(response.content)
            print(f"Downloaded {image_url} to {target_file}")
        except requests_exceptions.MissingSchema:
            print(f"{image_url} appears to be an invalid URL.")
        except requests_exceptions.ConnectionError:
            print(f"Could not connect to {image_url}.")

get_pictures = PythonOperator(
task_id="get_pictures", python_callable=_get_pictures, dag=dag
)

notify = BashOperator(
task_id="notify",
bash_command='echo "There are now $(ls /Users/asadali/airflow/images/ | wc -l) images."',
dag=dag,
)

download_launches >> get_pictures >> notify`

[enchant3dmango]

Can't help with the provided info, but I think you should check the storage and memory in the Airflow host, whether it's in a container or on your device.

I faced the "The scheduler does not appear to be running" issue several times back then, and the root cause was either out of storage or out of memory.