redis/redis-py · error · ConnectionError

Error setting client name

Error message

Error setting client name

What it means

Raised as a generic ConnectionError during on_connect() when CLIENT SETNAME <self.client_name> returns anything other than 'OK'. The library only sets the name if client_name was configured; a non-OK reply typically means an ACL restriction or a server that rejected the name. The handshake aborts and the connection is not usable.

Solutions

1. Grant the ACL user +client permission (or use a user with +@all).
2. Remove or simplify the client_name to confirm it is the cause, then re-add a sanitized value.
3. Upgrade the Redis server to >= 2.6.9.
4. If the name is only for diagnostics, move identification to LIB-NAME via driver_info instead.

Example fix

// before
r = redis.asyncio.Redis(host=h, client_name='my app name')
// after
r = redis.asyncio.Redis(host=h, client_name='my-app-name')

import redis.asyncio as aioredis

async def supports_client_setname(url: str, name: str) -> bool:
    r = aioredis.from_url(url)
    try:
        await r.execute_command('CLIENT', 'SETNAME', name)
        return True
    except Exception:
        return False
    finally:
        await r.aclose()

from redis.exceptions import ConnectionError

def is_client_name_error(exc: BaseException) -> bool:
    return isinstance(exc, ConnectionError) and 'client name' in str(exc).lower()

from redis.exceptions import ConnectionError

try:
    client = redis.asyncio.Redis(host=h, client_name=name)
    await client.ping()
except ConnectionError as e:
    if 'client name' in str(e).lower():
        client = redis.asyncio.Redis(host=h)  # drop client_name
    else:
        raise

When it happens

Trigger: Constructing redis.asyncio.Redis(client_name='my-app') (or setting client_name_class / pool client name) and connecting to a server whose ACL user lacks permission to run CLIENT SETNAME, or rejects the name value (e.g. contains invalid bytes).

Common situations: ACL user scoped with -client or renamed_commands blocking CLIENT; very old Redis server (< 2.6.9 where CLIENT SETNAME was introduced); a client_name containing spaces or newlines that the server rejects.

Related errors

• Invalid Database
• Invalid Username or Password
• Bad response from PING health check
• Buffer is closed.
• Cannot enable maintenance notifications for connection…

AI-assisted analysis of redis/redis-py@6a6b581b48 (2026-08-10). Data as JSON: /api/errors/d4e51ea90cb9fee2. Report an issue: GitHub.

Appendix: source

Thrown at redis/asyncio/connection.py:1025

            #     raise ConnectionError("Invalid RESP version")

        # Activate maintenance notifications for this connection
        # if enabled in the configuration
        # This is a no-op if maintenance notifications are not enabled
        await self.activate_maint_notifications_handling_if_enabled(
            check_health=check_health
        )

        # if a client_name is given, set it
        if self.client_name:
            await self.send_command(
                "CLIENT",
                "SETNAME",
                self.client_name,
                check_health=check_health,
            )
            if str_if_bytes(await self.read_response()) != "OK":
                raise ConnectionError("Error setting client name")

        # Set the library name and version from driver_info, pipeline for lower startup latency
        lib_name_sent = False
        lib_version_sent = False

        if self.driver_info and self.driver_info.formatted_name:
            await self.send_command(
                "CLIENT",
                "SETINFO",
                "LIB-NAME",
                self.driver_info.formatted_name,
                check_health=check_health,
            )
            lib_name_sent = True

        if self.driver_info and self.driver_info.lib_version:
            await self.send_command(
                "CLIENT",

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