apache/dubbo

traceId missing from MDC in logs in Dubbo 3.3.2

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#16165 opened on Mar 24, 2026

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 (2 comments) (0 reactions) (0 assignees)Java (41,524 stars) (26,453 forks)batch import
help wanted

Description

In Dubbo latest version 3.3.2, MDC.get("traceId") returns null even though the log pattern includes %X{traceId}. The call chain is web -> dubbo -> platform -> domains. Question: Is manual MDC.put required in a preHandler to propagate traceId?

Contributor guide

Tech stack
java
Domain
backend
Issue type
bug
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
3
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
1-3 hours
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
fresh
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
mostly clear
Prerequisites
JavaApache Dubbo basicsLogging with MDC
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
40
Research direction
Investigate how Dubbo's logging filter handles MDC context propagation. Check if traceId is set in MDC before RPC calls, and verify if the log pattern %X{traceId} is correctly configured. Look at the commit history or any linked PRs for recent changes to MDC handling in Dubbo 3.3.2. The question suggests that manual MDC.put may be needed; confirm if that's the expected behavior or if it's a regression.