apache/rocketmq · error · IllegalArgumentException

cidAll is null or cidAll empty

Error message

cidAll is null or cidAll empty

What it means

QueryAssignmentProcessor.allocate requires cidAll — the sorted list of all consumer ids in the group — to be non-empty. Empty cidAll means the broker's consumer-group connection table had no members for the group at assignment time.

Source

Thrown at broker/src/main/java/org/apache/rocketmq/broker/processor/QueryAssignmentProcessor.java:286

                //make sure each cid is assigned
                allocateResult = allocate(consumerGroup, clientId, mqAll, cidAll);
            }
        }

        return allocateResult;
    }

    private List<MessageQueue> allocate(String consumerGroup, String currentCID, List<MessageQueue> mqAll,
        List<String> cidAll) {
        if (StringUtils.isBlank(currentCID)) {
            throw new IllegalArgumentException("currentCID is empty");
        }

        if (CollectionUtils.isEmpty(mqAll)) {
            throw new IllegalArgumentException("mqAll is null or mqAll empty");
        }
        if (CollectionUtils.isEmpty(cidAll)) {
            throw new IllegalArgumentException("cidAll is null or cidAll empty");
        }

        List<MessageQueue> result = new ArrayList<>();
        if (!cidAll.contains(currentCID)) {
            log.info("[BUG] ConsumerGroup: {} The consumerId: {} not in cidAll: {}",
                consumerGroup,
                currentCID,
                cidAll);
            return result;
        }

        int index = cidAll.indexOf(currentCID);
        result.add(mqAll.get(index % mqAll.size()));
        return result;
    }

    private RemotingCommand setMessageRequestMode(ChannelHandlerContext ctx,
        RemotingCommand request) throws RemotingCommandException {

View on GitHub (pinned to 293f588571)

Solutions

1. Ensure at least one consumer of the group is registered (heartbeat ok) before assignment; retry the assignment request.
2. Check client-to-broker connectivity and that consumers aren't crashing at startup.
3. In exclusive-consume mode, avoid restarting 100% of a group's consumers at once.

catch (IllegalArgumentException e) { if (e.getMessage().contains("cidAll")) { waitAndRetryAssignmentAfterReconnect(); } else throw e; }

When it happens

Trigger: QUERY_ASSIGNMENT arrives for a group whose consumer-id list is empty (all members just disconnected, or consumer registration didn't complete) while mqAll is valid.

Common situations: All consumers of a group reconnecting simultaneously; consumer registered but heartbeat/registration lost; aggressive rebalancing churn during rolling restarts.

Related errors

• currentCID is empty
• mqAll is null or mqAll empty
• subscription group list is empty.
• group is null.
• subscribe lite operation is not supported for this group

AI-assisted analysis of apache/rocketmq@293f588571 (2026-08-14). Data as JSON: /api/errors/7e35c199a90add30. Report an issue: GitHub.