redis-py EVAL_RO, EVALSHA_RO doesn't get routed to replicas

The Fix

pip install redis==7.1.0

Based on closed redis/redis-py issue #2490 · PR/commit linked

Production note: Most teams hit this during upgrades or environment changes. Roll out with a canary and smoke critical endpoints (health, OpenAPI/docs) before 100%.

Open PR/Commit

@@ -52,6 +52,8 @@
         "BITCOUNT",
         "BITPOS",
+        "EVAL_RO",
+        "EVALSHA_RO",
         "EXISTS",

fix.md

Option A — Upgrade to fixed release\npip install redis==7.1.0\nWhen NOT to use: This fix is not applicable if using a Redis version prior to 7.0.\n\n

Why This Fix Works in Production

Trigger: EVAL_RO, EVALSHA_RO doesn't get routed to replicas
Mechanism: READ_COMMANDS was missing EVAL_RO and EVALSHA_RO, preventing routing to replicas
Why the fix works: Fixes issue #2490 by adding EVAL_RO and EVALSHA_RO to the READ_COMMANDS list, allowing these commands to be routed to replicas. (first fixed release: 7.1.0).

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 3.5.1 in real deployments (not just unit tests).
READ_COMMANDS was missing EVAL_RO and EVALSHA_RO, preventing routing to replicas
Production symptom (often without a traceback): EVAL_RO, EVALSHA_RO doesn't get routed to replicas

Proof / Evidence

GitHub issue: #2490
Fix PR: https://github.com/redis/redis-py/pull/2494
First fixed release: 7.1.0
Reproduced locally: No (not executed)
Last verified: 2026-02-07
Confidence: 0.85
Did this fix it?: Yes (upstream fix exists)
Own content ratio: 0.79

Discussion

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

Jump to Sources Open on GitHub

“Since the fix for this is merged, is this statement The following commands are not supported: - EVAL_RO - EVALSHA_RO in https://github.com/redis/redis-py/blob/master/docs/lua_scripting.rst#cluster-mode still valid?”

@bluecrabs007 · 2023-08-01 · confirmation · source

“@zakaf The reason these aren't in the READ_COMMANDS list is purely historic - they came after the list, in the redis 7 release. We'd love…”

@chayim · 2022-12-07 · source

Failure Signature (Search String)

EVAL_RO, EVALSHA_RO doesn't get routed to replicas
**Description**: Description of your issue, stack traces from errors and code that reproduces the issue

Copy-friendly signature

signature.txt

Failure Signature
-----------------
EVAL_RO, EVALSHA_RO doesn't get routed to replicas
**Description**: Description of your issue, stack traces from errors and code that reproduces the issue

Error Message

Signature-only (no traceback captured)

error.txt

Error Message
-------------
EVAL_RO, EVALSHA_RO doesn't get routed to replicas
**Description**: Description of your issue, stack traces from errors and code that reproduces the issue

Environment

Python: 3.5.1

What Broke

Commands EVAL_RO and EVALSHA_RO are always directed to the master, causing inefficiencies.

Why It Broke

READ_COMMANDS was missing EVAL_RO and EVALSHA_RO, preventing routing to replicas

Fix Options (Details)

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

pip install redis==7.1.0

When NOT to use: This fix is not applicable if using a Redis version prior to 7.0.

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/2494

First fixed release: 7.1.0

Last verified: 2026-02-07. Validate in your environment.

When NOT to Use This Fix

This fix is not applicable if using a Redis version prior to 7.0.

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.

Version Compatibility Table

Version	Status
7.1.0	Fixed

Related Issues

No related fixes found.

Cluster: redis-py:configuration-error redis-py hub redis-py best practices All hubs All clusters

Related clusters: Retry storm Data consistency Race condition

Sources

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

redis-py EVAL_RO, EVALSHA_RO doesn't get routed to replicas (Fix)