[KAFKA-9272] Error when trying to connect to SSL port using PLAINTEXT is very confusing

• Type: Bug
• Status: Open
• Priority: Minor
• Resolution: Unresolved
• Affects Version/s: 2.2.1
• Component/s: clients
• Assignee: Unassigned
• Reporter: Richard Wise
• Created: 05/Dec/19 10:52
• Updated: 05/Dec/19 10:52

Description

I accidentally forgot to set `security.protocol` to SSL when connecting to an SSL port, so connected via PLAINTEXT. I expected the Kafka client to fail immediately with a message about mismatched security protocols, but instead it failed saying that the topic does not exist and auto-creation was not enabled.

This error message is very misleading and leads developers to think that the problem is the server configuration, not the client network security settings.