Celery Celery worker aborts without any message (Fix)

The Fix

pip install celery==5.3.1

Based on closed celery/celery issue #8310 · 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.

Jump to Verify Open PR/Commit

@@ -1 +1 @@
@@ -1 +1 @@
-redis>=4.5.2
+redis>=4.5.2,!=4.5.5

repro.py

celery -A uniweb report

software -> celery:5.2.7 (dawn-chorus) kombu:5.3.0 py:3.9.17
            billiard:3.6.4.0 redis:4.5.4
platform -> system:Linux arch:64bit
            kernel version:3.10.0-1160.88.1.el7.x86_64 imp:CPython
loader   -> celery.loaders.app.AppLoader
settings -> transport:sentinel results:redis://:**@django-cms-test-redis-headless:6379/7

verify

Re-run the minimal reproduction on your broken version, then apply the fix and re-run.

fix.md

Option A — Upgrade to fixed release\npip install celery==5.3.1\nWhen NOT to use: Do not use if it changes public behavior or if the failure cannot be reproduced.\n\n

Why This Fix Works in Production

Trigger: celery.worker - start - CRITICAL - Unrecoverable error: TypeError("SentinelManagedConnection.read_response() got an unexpected keyword argument…
Mechanism: Restricts the use of Redis version 4.5.5 due to severe bugs that cause Celery workers to crash without any message.
Why the fix works: Restricts the use of Redis version 4.5.5 due to severe bugs that cause Celery workers to crash without any message. (first fixed release: 5.3.1).

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

Shows up under Python 3.10 in real deployments (not just unit tests).
Surfaces as: celery.worker - start - CRITICAL - Unrecoverable error: TypeError("SentinelManagedConnection.read_response() got an unexpected keyword argument 'disconnect_on_error'")

Proof / Evidence

GitHub issue: #8310
Fix PR: https://github.com/celery/celery/pull/8317
First fixed release: 5.3.1
Reproduced locally: No (not executed)
Last verified: 2026-02-09
Confidence: 0.95
Did this fix it?: Yes (upstream fix exists)
Own content ratio: 0.40

Discussion

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

Jump to Sources Open on GitHub

“Found the problem: This was caused by https://github.com/redis/redis-py/commit/c0833f60a1d9ec85c589004aba6b6739e6298248 which changed how internally redis-py handles connection, unfortunatelly the Sentinel wrapper was not updated to reflect that…”

@sevdog · 2023-06-20 · source

“Hey @jrief :wave:, Thank you for opening an issue”

@open-collective-bot · 2023-06-12 · source

“> Our setup is Celery with Redis over Sentinel in a Kubernetes cluster”

@auvipy · 2023-06-12 · source

“I should have mentioned redis-py. A hint on this would be useful, it took me almost a day to find the culprit. As I said,…”

@jrief · 2023-06-12 · source

Failure Signature (Search String)

celery.worker - start - CRITICAL - Unrecoverable error: TypeError("SentinelManagedConnection.read_response() got an unexpected keyword argument 'disconnect_on_error'")

Error Message

Stack trace

error.txt

Error Message
-------------
celery.worker - start - CRITICAL - Unrecoverable error: TypeError("SentinelManagedConnection.read_response() got an unexpected keyword argument 'disconnect_on_error'")
Traceback (most recent call last):
  File "/opt/venv/lib/python3.10/site-packages/celery/worker/worker.py", line 203, in start
    self.blueprint.start(self)
  File "/opt/venv/lib/python3.10/site-packages/celery/bootsteps.py", line 116, in start
    step.start(parent)
  File "/opt/venv/lib/python3.10/site-packages/celery/bootsteps.py", line 365, in start
    return self.obj.start()
  File "/opt/venv/lib/python3.10/site-packages/celery/worker/consumer/consumer.py", line 332, in start
    blueprint.start(self)
  File "/opt/venv/lib/python3.10/site-packages/celery/bootsteps.py", line 116, in start
    step.start(parent)
  File "/opt/venv/lib/python3.10/site-packages/celery/worker/consumer/consumer.py", line 628, in start
    c.loop(*c.loop_args())
  File "/opt/venv/lib/python3.10/site-packages/celery/worker/loops.py", line 97, in asynloop
    next(loop)
  File "/opt/venv/lib/python3.10/site-packages/kombu/asynchronous/hub.py", line 373, in create_loop
    cb(*cbargs)
  File "/opt/venv/lib/python3.10/site-packages/kombu/transport/redis.py", line 1336, in on_readable
    self.cycle.on_readable(fileno)
  File "/opt/venv/lib/python3.10/site-packages/kombu/transport/redis.py", line 566, in on_readable
    chan.handlers[t
... (truncated) ...

Minimal Reproduction

repro.py

celery -A uniweb report

software -> celery:5.2.7 (dawn-chorus) kombu:5.3.0 py:3.9.17
            billiard:3.6.4.0 redis:4.5.4
platform -> system:Linux arch:64bit
            kernel version:3.10.0-1160.88.1.el7.x86_64 imp:CPython
loader   -> celery.loaders.app.AppLoader
settings -> transport:sentinel results:redis://:**@django-cms-test-redis-headless:6379/7

Environment

Python: 3.10

What Broke

Celery workers abort without any message, leading to task processing failures.

Fix Options (Details)

Option A — Upgrade to fixed release Safe default (recommended)

pip install celery==5.3.1

When NOT to use: Do not use if it changes public behavior or if the failure cannot be reproduced.

Use when you can deploy the upstream fix. It is usually lower-risk than long-lived workarounds.

Option D — Guard side-effects with OnceOnly Guardrail for side-effects

Mitigate duplicate external side-effects under retries/timeouts/agent loops by gating the operation before calling external systems.

Place OnceOnly between your code/agent and real side-effects (Stripe, emails, CRM, APIs).
Use a stable key per side-effect (e.g., customer_id + action + idempotency_key).
Fail-safe: configure fail-open vs fail-closed based on blast radius and spend risk.

Show example snippet (optional)

onceonly.py

from onceonly import OnceOnly
import os

once = OnceOnly(api_key=os.environ["ONCEONLY_API_KEY"], fail_open=True)

# Stable idempotency key per real side-effect.
# Use a request id / job id / webhook delivery id / Stripe event id, etc.
event_id = "evt_..."  # replace
key = f"stripe:webhook:{event_id}"

res = once.check_lock(key=key, ttl=3600)
if res.duplicate:
    return {"status": "already_processed"}

# Safe to execute the side-effect exactly once.
handle_event(event_id)

See OnceOnly SDK

When NOT to use: Do not use this to hide logic bugs or data corruption. Use it to block duplicate external side-effects and enforce tool permissions/spend caps.

Fix reference: https://github.com/celery/celery/pull/8317

First fixed release: 5.3.1

Last verified: 2026-02-09. Validate in your environment.

When NOT to Use This Fix

Do not use if it changes public behavior or if the failure cannot be reproduced.
Do not use this to hide logic bugs or data corruption. Use it to block duplicate external side-effects and enforce tool permissions/spend caps.

Verify Fix

verify

Re-run the minimal reproduction on your broken version, then apply the fix and re-run.

Did This Fix Work in Your Case?

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

Prevention

Add a TLS smoke test that performs a real handshake in CI (include CA bundle validation and hostname checks).
Alert on handshake failures by error string and endpoint to catch cert/CA changes quickly.

Version Compatibility Table

Version	Status
5.3.1	Fixed

Related Issues

No related fixes found.

Cluster: celery:configuration-error Celery hub Celery best practices All hubs All clusters

Related clusters: Data consistency Duplicates Duplicate processing

Sources

We don’t republish the full GitHub discussion text. Use the links above for context.