KubeBlocks
BlogsEnterprise
⌘K
​
Blogs

Overview
Quickstart
Architecture

Operations

Stop / Start / Restart
Vertical Scaling
Horizontal Scaling
Volume Expansion
Reconfigure
Manage Services

Observability

Prometheus Integration
  1. Architecture
  2. Broker Sharding
  3. Supported Versions
  4. Key Features
  5. Limitations

KubeBlocks for RocketMQ

Apache RocketMQ is a distributed messaging and streaming platform with low latency, high performance, high reliability, trillion-level capacity, and flexible scalability. KubeBlocks provides production-ready RocketMQ cluster management on Kubernetes.

Architecture

A RocketMQ cluster managed by KubeBlocks consists of four components:

ComponentRoleDescription
NameServer (namesrv)RoutingLightweight service discovery and routing. Producers and consumers connect here to find brokers.
Broker (broker)MessagingStores and delivers messages. Deployed as shards, each shard has a master and optional slaves.
Dashboard (dashboard)Management UIWeb console for cluster administration, topic management, and consumer group monitoring.
Exporter (exporter)ObservabilityPrometheus metrics exporter for broker statistics (topics, queues, consumer lag).
Producers → NameServer (routing) → Broker Shard 0 (master + slaves)
Consumers ↗                      → Broker Shard 1 (master + slaves)
                                   ...

Broker Sharding

Brokers in KubeBlocks use a sharding model. Each shard is an independent broker group with one master and zero or more slaves:

  • 2 shards × 1 replica = 2 broker pods (masters only, no HA)
  • 2 shards × 2 replicas = 4 broker pods (1 master + 1 slave per shard)

Shards handle different partitions of topics, allowing horizontal capacity scaling.

Supported Versions

RocketMQ VersionKubeBlocks Addon Version
4.9.61.0.2

Key Features

  • Master-Slave replication: Each broker shard supports master-slave async replication
  • Dynamic parameter reconfiguration: 165+ broker parameters can be updated live without restart
  • Role detection: KubeBlocks automatically detects master/slave roles via role probe
  • Graceful scale-in: Broker shard removal checks for unconsumed messages before deletion
  • ACL support: Optional access control with HMAC-SHA1 request signing
  • Prometheus monitoring: Built-in JMX exporter (JVM metrics) and RocketMQ exporter (broker metrics)
  • Web Dashboard: Optional RocketMQ Dashboard for cluster management

Limitations

  • No backup/restore: KubeBlocks does not provide built-in backup for RocketMQ data. Use Kubernetes volume snapshots for data protection.
  • No switchover: Manual master-slave failover is not supported via KubeBlocks OpsRequests. RocketMQ handles failover at the broker level.
  • Broker replica scaling: You cannot increase/decrease replicas within a shard via OpsRequest; adjust shards count instead.

© 2026 KUBEBLOCKS INC