redis/jedis · error · UnsupportedOperationException

Command '' with request policy cannot be executed in…

Error message

Command '' with  request policy cannot be executed in pipeline mode because it cannot be routed to a single slot. This command has no keys to determine routing. Use non-pipeline cluster client for this command.

What it means

Cluster pipelines (MultiNodePipelineBase) can only execute commands whose keys map to a single hash slot, because each command is sent to one node. validatePipelineCommand rejects commands with a request policy whose keys are absent or spread across multiple slots by throwing UnsupportedOperationException.

Solutions

Execute the command directly on RedisClusterClient (non-pipeline) instead of the pipeline.
For multi-key commands, hash-tag the keys (e.g. {user1}:a, {user1}:b) so they map to one slot.
Remove keyless commands from the pipeline and batch them separately.
For FLUSH-style broad commands, iterate nodes or use dedicated per-node APIs.

Example fix

// before
try (Pipeline p = clusterClient.pipelined()) {
  p.set("a", "1");
  p.mset("b", "2", "c", "3"); // keys map to multiple slots -> throws
}

// after
try (Pipeline p = clusterClient.pipelined()) {
  p.set("{h1}a", "1");
  p.mset("{h1}b", "2", "{h1}c", "3"); // same hash tag, single slot
}

Defensive patterns

Strategy: fallback

Validate before calling

// pre-flight: verify all keys of the command share one slot
String tag = key.contains("{") ? key.substring(key.indexOf('{') + 1, key.indexOf('}')) : key;
int slot = JedisClusterHashSlotUtil.getHashSlot(SafeEncoder.encode("{" + tag + "}"));
// only append to pipeline if every key hashes to the same slot

Try / catch

try {
  pipeline.appendCommand(commandObject);
} catch (UnsupportedOperationException e) {
  // execute outside the pipeline instead
  clusterClient.sendCommand(commandObject);
}

Prevention

Use hash tags ({tag}) on related keys to keep them in one slot.
Keep keyless commands (PING, INFO) out of cluster pipelines.
Wrap pipeline building so unsupported commands fall back to direct execution.
Review the command's request policy before adding module commands to pipelines.

When it happens

Trigger: Appending to a cluster pipeline a command with no keys (e.g. PING, INFO, RANDOMKEY) or with keys hashing to multiple slots (e.g. MSET with keys on different slots) — including unkeyed custom/module commands.

Common situations: Migrating a standalone Jedis pipeline to a cluster pipeline; using commands without keys in pipelined mode; empty CommandObject argument lists.

Understand the failure class

Background: UnsupportedOperationException and "is not supported" errors: when a library deliberately refuses a call — this error's family across 30 libraries.

Related errors

AI-assisted analysis of redis/jedis@6dac31d4c2 (2026-09-08). Data as JSON: /api/errors/787ce6da5c839412. Report an issue: GitHub.

Appendix: source

Thrown at src/main/java/redis/clients/jedis/MultiNodePipelineBase.java:236

    CommandFlagsRegistry.RequestPolicy policy =
        commandFlagsRegistry.getRequestPolicy(args);

    // For multi-node policies, check if the command can be routed to a single slot
    switch (policy) {
      case ALL_SHARDS:
      case MULTI_SHARD:
      case ALL_NODES:
      case SPECIAL:
        // If the command has keys that route to a single slot, allow it
        Set<Integer> slots = args.getKeyHashSlots();
        if (slots.size() == 1) {
          // Command can be routed to a single slot - allow it
          return;
        }

        // Command cannot be routed to a single slot - reject it
        String policyName = policy.name();
        throw new UnsupportedOperationException(
            "Command '" + args.getCommand() + "' with " + policyName + " request policy "
                + "cannot be executed in pipeline mode because it cannot be routed to a single slot. "
                + (slots.isEmpty()
                    ? "This command has no keys to determine routing. "
                    : "This command's keys map to multiple slots (" + slots.size() + " slots). ")
                + "Use non-pipeline cluster client for this command.");

      case DEFAULT:
      default:
        // DEFAULT policy and unknown policies - allow standard command execution
        // Routes to single node based on key hash
        break;
    }
  }

  @Deprecated
  public Response<Long> waitReplicas(int replicas, long timeout) {
    return appendCommand(commandObjects.waitReplicas(replicas, timeout));

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