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Details

The Fix

Fixes an invalid configuration key in the Kafka broker demo, changing 'bootstrap_servers' to 'bootstrap.servers'.

Based on closed celery/celery issue #10011 · PR/commit linked

Production note: This usually shows up under retries/timeouts. Treat it as a side-effect risk until you can verify behavior with a canary + real traffic.

Open PR/Commit
@@ -41,7 +41,7 @@ For celeryconfig.py: "security.protocol": "SASL_SSL", "sasl.mechanism": "SCRAM-SHA-512", - "bootstrap_servers": "broker:9094", + "bootstrap.servers": "broker:9094", }
fix.md
Option A — Apply the official fix\nFixes an invalid configuration key in the Kafka broker demo, changing 'bootstrap_servers' to 'bootstrap.servers'.\nWhen NOT to use: Do not apply this fix if using a different Kafka client that supports 'bootstrap_servers'.\n\n

Why This Fix Works in Production

  • Trigger: cimpl.KafkaException: KafkaError{code=_INVALID_ARG,val=-186,str="No such configuration property: "bootstrap_servers""}
  • Mechanism: Fixes an invalid configuration key in the Kafka broker demo, changing 'bootstrap_servers' to 'bootstrap.servers'.
Production impact:
  • If left unfixed, the same config can fail only in production (env differences), causing startup failures or partial feature outages.

Why This Breaks in Prod

  • Surfaces as: cimpl.KafkaException: KafkaError{code=_INVALID_ARG,val=-186,str="No such configuration property: "bootstrap_servers""}

Proof / Evidence

Discussion

High-signal excerpts from the issue thread (symptoms, repros, edge-cases).

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Issue thread · issue description · source

Failure Signature (Search String)

  • cimpl.KafkaException: KafkaError{code=_INVALID_ARG,val=-186,str="No such configuration property: "bootstrap_servers""}

Error Message

Stack trace
error.txt
Error Message ------------- cimpl.KafkaException: KafkaError{code=_INVALID_ARG,val=-186,str="No such configuration property: "bootstrap_servers""}

What Broke

Users encounter a Kafka error when starting the worker due to incorrect configuration.

Fix Options (Details)

Option A — Apply the official fix

Fixes an invalid configuration key in the Kafka broker demo, changing 'bootstrap_servers' to 'bootstrap.servers'.

When NOT to use: Do not apply this fix if using a different Kafka client that supports 'bootstrap_servers'.

Fix reference: https://github.com/celery/celery/pull/10060

Last verified: 2026-02-08. Validate in your environment.

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When NOT to Use This Fix

  • Do not apply this fix if using a different Kafka client that supports 'bootstrap_servers'.

Did This Fix Work in Your Case?

Quick signal helps us prioritize which fixes to verify and improve.

Prevention

  • Capture the exact failing error string in logs and tests so you can reproduce via a minimal script.
  • Pin production dependencies and upgrade only with a reproducible test that hits the failing path.

Related Issues

No related fixes found.

Sources

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