AWS MWAA does not see dags and there is no logs in cloud watch

To resolve the issue of AWS MWAA not seeing DAGs and the absence of logs in CloudWatch, you can try the following steps:

1. Verify task log settings: Ensure that you have enabled task logs at the 'INFO' level for your MWAA environment. This is crucial for viewing Airflow logs in Amazon CloudWatch.

2. Check environment execution role: Double-check that the environment execution role has the correct permission policies. This includes permissions for accessing the S3 bucket containing your DAGs and for writing logs to CloudWatch.

3. Validate DAG file structure: Make sure your DAG files are properly structured and don't contain any syntax errors. Incorrect DAG syntax can prevent MWAA from processing the files.

4. Review Python dependencies: Verify that your DAGs have the appropriate Python libraries to load. You can use the Amazon MWAA local-runner tool to test your Python dependencies and eliminate imports until you find the one causing the issue.

5. Check S3 bucket permissions: Ensure that the MWAA environment has the necessary permissions to access the S3 bucket where your DAG files are stored.

6. Examine CloudWatch metrics: Review the 'CPUUtilization' and 'MemoryUtilization' CloudWatch metrics for your MWAA environment. High CPU and memory usage can cause issues with DAG processing and UI access.

7. Investigate potential resource contention: If there are resource contention issues, you might receive an "Oops, something bad has happened" error or 5xx errors when accessing the Airflow UI. To troubleshoot, try removing all Python files from your environment's DAGs location in S3, then add them back one at a time while monitoring for changes in UI access or performance.

8. Check Python package versions: Incompatible Python package versions can cause Airflow UI access issues and prevent DAG processing. Review your requirements.txt file for any incompatible dependencies or missing constraints.

9. Run MWAA verify script: Use the Amazon MWAA verify script to check for any configuration issues that might be preventing proper functioning of your environment.

10. Test connectivity: Ensure that there are no network connectivity issues between your MWAA environment and the necessary AWS services (S3, CloudWatch).

If after trying these steps you still encounter issues, you may need to contact AWS support for further assistance.
Sources
Troubleshooting: CloudWatch Logs and CloudTrail errors - Amazon Managed Workflows for Apache Airflow
Troubleshoot Apache Airflow UI access issues in MWAA | AWS re:Post