redis-py Retry Mechanism Fails When Redis Container is

The Fix

pip install redis==7.1.1

Based on closed redis/redis-py issue #3555 · 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

@@ -296,7 +296,14 @@ def set_parser(self, parser_class: Type[BaseParser]) -> None:
     async def connect(self):
         """Connects to the Redis server if not already connected"""
-        await self.connect_check_health(check_health=True)
+        # try once the socket connect with the handshake, retry the whole
+        # connect/handshake flow based on retry policy

repro.py

ping_parts = self._command_packer.pack("PING")
for part in ping_parts:
    sock.sendall(part)

    response = sock.recv(7)

    if not str_if_bytes(response).startswith("+PONG"):
        raise OSError(f"Redis handshake failed: unexpected response {response!r}")

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 redis==7.1.1\nWhen NOT to use: This fix is not suitable if the connection logic does not require retries.\n\n

Why This Fix Works in Production

Trigger: Retry Mechanism Fails When Redis Container is Paused
Mechanism: Adds retries for both the socket connection and the initial connection handshake, improving retry behavior when the Redis container is paused.
Why the fix works: Adds retries for both the socket connection and the initial connection handshake, improving retry behavior when the Redis container is paused. (first fixed release: 7.1.1).

Production impact:

If left unfixed, retry loops can amplify load and turn a small outage into a cascade (thundering herd).

Why This Breaks in Prod

Production symptom (often without a traceback): Retry Mechanism Fails When Redis Container is Paused

Proof / Evidence

GitHub issue: #3555
Fix PR: https://github.com/redis/redis-py/pull/3863
First fixed release: 7.1.1
Reproduced locally: No (not executed)
Last verified: 2026-02-08
Confidence: 0.80
Did this fix it?: Yes (upstream fix exists)
Own content ratio: 0.55

Discussion

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

Jump to Sources Open on GitHub

“Hi! We would have a look on this in meantime”

@vladvildanov · 2025-03-13 · source

“Hey @vladvildanov , I opened a PR with a solution to problem mentioned in the comment. if you want I can add you as a…”

@ManelCoutinhoSensei · 2025-04-11 · source

“Hi @ManelCoutinhoSensei, can you provide small example how you end up with the provided log of the performed retries? I tried to reproduce it, and…”

@petyaslavova · 2025-09-17 · source

“Following up on this issue, I've noticed that it also occurs when a container is still booting up in the background, making the port available…”

@ManelCoutinhoSensei · 2025-03-17 · source

Failure Signature (Search String)

Retry Mechanism Fails When Redis Container is Paused
When the Redis container is **paused** (not stopped), the connection attempt should fail, triggering the retry mechanism. The retry number should increase monotonically until the

Copy-friendly signature

signature.txt

Failure Signature
-----------------
Retry Mechanism Fails When Redis Container is Paused
When the Redis container is **paused** (not stopped), the connection attempt should fail, triggering the retry mechanism. The retry number should increase monotonically until the specified maximum number of retries is reached.

Error Message

Signature-only (no traceback captured)

error.txt

Error Message
-------------
Retry Mechanism Fails When Redis Container is Paused
When the Redis container is **paused** (not stopped), the connection attempt should fail, triggering the retry mechanism. The retry number should increase monotonically until the specified maximum number of retries is reached.

Minimal Reproduction

repro.py

ping_parts = self._command_packer.pack("PING")
for part in ping_parts:
    sock.sendall(part)

    response = sock.recv(7)

    if not str_if_bytes(response).startswith("+PONG"):
        raise OSError(f"Redis handshake failed: unexpected response {response!r}")

What Broke

Retry mechanism gets stuck at the first attempt, repeating indefinitely.

Fix Options (Details)

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

pip install redis==7.1.1

When NOT to use: This fix is not suitable if the connection logic does not require retries.

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

Fix reference: https://github.com/redis/redis-py/pull/3863

First fixed release: 7.1.1

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

When NOT to Use This Fix

This fix is not suitable if the connection logic does not require retries.

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.
Make timeouts explicit and test them (unit + integration) to avoid silent behavior changes.
Instrument retries (attempt count + reason) and alert on spikes to catch dependency slowdowns.

Version Compatibility Table

Version	Status
7.1.1	Fixed

Related Issues

No related fixes found.

Cluster: redis-py:retry-storm redis-py hub redis-py best practices All hubs All clusters

Related clusters: Configuration error Data consistency Race condition

Sources

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

redis-py Retry Mechanism Fails When Redis Container is Paused (Fix)