[KAFKA-13625] Fix inconsistency in dynamic application log levels

• Type: Improvement
• Status: In Progress
• Priority: Minor
• Resolution: Unresolved
• Component/s: core
• Assignee: Dongjin Lee
• Reporter: Dongjin Lee
• Created: 28/Jan/22 09:48
• Updated: 04/Feb/22 07:56

Description

As of present, there are two ways of changing log levels in Runtime:

1. JMX API
2. Admin API

However, there are some inconsistencies between these two ways;

1. JMX API allows OFF level; but Admin API does not. If the user tries to set the logger's level to OFF, Kafka responds with INVALID_CONFIG (40) error.
2. JMX API converts unsupported log level to DEBUG; but Admin API throws an error. The documentation does not state this difference in semantics.

To fix these inconsistencies, we have to:

1. Add OFF level to LogLevelConfig.
2. Add documentation on different semantics between JMX and Admin API.

Issue Links

• is related to: KAFKA-9366 Upgrade log4j to log4j2
• is related to: KAFKA-7800 Extend Admin API to support dynamic application log levels
• links to: GitHub Pull Request #11720