ProxySQL + PostgreSQL: JDBC clients (DBeaver/IntelliJ) failing with EOFException while native clients work

[Divyansh Kohli]

Hello everyone,

I’m looking for some guidance regarding ProxySQL’s PostgreSQL interface and its behavior with JDBC-based clients.

We’re observing that native PostgreSQL clients connect and work without any issues, while JDBC-based IDE clients consistently fail during connection initialization.

Working clients:

• psql (native PostgreSQL CLI)
• TablePlus
• pgAdmin
• Postico

Failing clients:

• DBeaver
• IntelliJ IDEA Database plugin

The JDBC clients fail with the following error during the handshake phase:

EOFException: The connection attempt failed

This happens before any query execution. Authentication, SSL, and backend connectivity are all verified to be working, as native clients connect reliably through the same ProxySQL setup.

Is this a known limitation of ProxySQL’s PostgreSQL interface when used with JDBC-based clients, or is there a recommended configuration or workaround that allows tools like DBeaver or IntelliJ to connect reliably?

Any insights, experiences, or pointers to documentation would be greatly appreciated.
Thanks in advance for your help!

Best regards,
Divyansh

[David Stokes]

Can you share your connector string?  ODBC/JSBC connection strings can be tricky.