python network_error ai_generated true

sqlalchemy.exc.OperationalError: (psycopg2.OperationalError) could not connect to server: Connection refused Is the server running on host "localhost" (::1) and accepting TCP/IP connections on port 5432?

ID: python/sqlalchemy-connection-refused

Also available as: JSON · Markdown · 中文
80%Fix Rate
85%Confidence
0Evidence
2025-06-01First Seen

Version Compatibility

VersionStatusIntroducedDeprecatedNotes
3.x active — — —

Root Cause

The database server is not running or not accepting connections on the specified host and port.

generic

中文

数据库服务器未运行或未在指定的主机和端口上接受连接。

Workarounds

  1. 95% success Start the database server 
    # For PostgreSQL:
sudo systemctl start postgresql
# Or:
pg_ctl start
  2. 90% success Check if the server is listening on the correct interface 
    sudo netstat -tulpn | grep 5432
# If not, edit postgresql.conf to listen on '*' or '0.0.0.0'

Dead Ends

Common approaches that don't work:

  1. Changing the port number arbitrarily 80% fail

    The database is not listening on that port either.

  2. Disabling firewall completely 60% fail

    This is a security risk and may not solve the issue if the server is not running.