Airflow scheduler stops with exception

Question

I have attached the error message along the question

ERROR - Exception when executing SchedulerJob._run_scheduler_loop
Traceback (most recent call last):
  File "/home/centos/env_airflow/lib64/python3.6/site-packages/sqlalchemy/engine/base.py", line 1277, in _execute_context
    cursor, statement, parameters, context
  File "/home/centos/env_airflow/lib64/python3.6/site-packages/sqlalchemy/engine/default.py", line 608, in do_execute
    cursor.execute(statement, parameters)
psycopg2.OperationalError: server closed the connection unexpectedly
        This probably means the server terminated abnormally
        before or while processing the request.

Answer 1

The PostgreSQL database server closed the connection unexpectedly. Look into the PostgreSQL log file for an explanation.

There you will either find an error message that explains the reason, or you will find a similar message (unexpected connection loss), which would indicate that a malicious firewall or router is interrupted the network connection.