redis/redis-py · error · RedisError

{cmd_name.upper()} command doesn't exist in Redis commands

Error message

{cmd_name.upper()} command doesn't exist in Redis commands

What it means

Raised by the sync CommandsParser.get_keys() when, after splitting the command name (e.g. 'memory' from 'memory usage') and re-running COMMAND to refresh the cache, the command is still unknown. The cluster client uses get_keys() to compute the slot for a command, so an unknown command cannot be routed. The error is a plain RedisError and includes the upper-cased command name.

Source

Thrown at redis/_parsers/commands.py:150

        if len(args) < 2:
            # The command has no keys in it
            return None

        cmd_name = args[0].lower()
        if cmd_name not in self.commands:
            # try to split the command name and to take only the main command,
            # e.g. 'memory' for 'memory usage'
            cmd_name_split = cmd_name.split()
            cmd_name = cmd_name_split[0]
            if cmd_name in self.commands:
                # save the split command to args
                args = cmd_name_split + list(args[1:])
            else:
                # We'll try to reinitialize the commands cache, if the engine
                # version has changed, the commands may not be current
                self.initialize(redis_conn)
                if cmd_name not in self.commands:
                    raise RedisError(
                        f"{cmd_name.upper()} command doesn't exist in Redis commands"
                    )

        command = self.commands.get(cmd_name)
        if "movablekeys" in command["flags"]:
            keys = self._get_moveable_keys(redis_conn, *args)
        elif "pubsub" in command["flags"] or command["name"] == "pubsub":
            keys = self._get_pubsub_keys(*args)
        else:
            if (
                command["step_count"] == 0
                and command["first_key_pos"] == 0
                and command["last_key_pos"] == 0
            ):
                is_subcmd = False
                if "subcommands" in command:
                    subcmd_name = f"{cmd_name}|{args[1].lower()}"
                    for subcmd in command["subcommands"]:

View on GitHub (pinned to da03cdc7e8)

Solutions

Verify the command exists on the server with 'redis-cli COMMAND INFO <name>'.
Ensure any required module (RediSearch/JSON/Bloom/Timeseries) is loaded on every cluster node.
Check the calling user has permissions to run COMMAND (ACL) so the parser cache is populated.
Spell the command exactly as Redis knows it (case-insensitive, but no extra spaces).

Example fix

// before
await rc.execute_command("FT.SEARCH", "idx", "foo")  # module not loaded

// after
# load the module on each master, or use an image with RediSearch:
#   redis-server --loadmodule /path/redisearch.so
await rc.execute_command("FT.SEARCH", "idx", "foo")

Defensive patterns

Strategy: validation

Validate before calling

# Validate the command is known before issuing through the cluster client
import redis
def command_known(rc, name):
    info = rc.command(name)
    return bool(info)
# usage
if not command_known(rc, "MEMORY"):
    raise ValueError("MEMORY not available on this cluster")

Try / catch

try:
    rc.execute_command("FOO.BAR", "k")
except redis.exceptions.RedisError as e:
    if "command doesn't exist in Redis commands" in str(e):
        # command unknown / module missing; do not retry blindly
        raise

Prevention

Run 'redis-cli COMMAND INFO <name>' on every node before issuing new commands.
Load required modules (RediSearch/JSON/Bloom) on all masters.
Grant the ACL user permission to run COMMAND so the cache is complete.
Spell command names exactly; pass multi-word commands as root + subcommand.

When it happens

Trigger: Calling an unknown or misspelled command through RedisCluster.execute_command(); a command from a Redis module that is not loaded on the node that answered COMMAND; a command whose name the cluster client cannot split into a known root; passing a fully-qualified module command like 'ft.search' when the search module is absent.

Common situations: RedisStack module not loaded (RediSearch, RedisJSON, RedisBloom) but client issues a module command; typo in command name; targeting a Redis < the version that introduced the command; COMMAND was ACL-restricted so the cache came back incomplete.

Related errors

AI-assisted analysis of redis/redis-py@da03cdc7e8 (2026-08-04). Data as JSON: /data/errors/cad792ceb8a076d9.json. Report an issue: GitHub.