MySQL InnoDB Cluster + Group Replication + MySQL Router Topology

Native MySQL high-availability architecture driven by Paxos group replication protocol. Runs in single-primary mode to eliminate write conflicts and routes traffic transparently via MySQL Router.

Components:MySQL ShellMySQL RouterGroup ReplicationInnoDB Storage EngineMySQL Enterprise Backup

Architecture Topology & Flow Diagram

📌 MySQL InnoDB Cluster + Group Replication + MySQL Router Reference Architecture Diagram (Single-Primary Mode)

Topology Blueprint

3x MySQL Enterprise / Community Node + 2x MySQL Router + Paxos Quorum

Client Ingress & Routing Flow

11. Application Layer & Router

Web, Mobile, and Analytics clients connect to MySQL Router on port 6446 (R/W) and port 6447 (R/O).

22. Metadata Cache Dynamic Routing

MySQL Router maintains a live metadata cache of cluster topology to dispatch read and write traffic without client reconfiguration.

33. Group Replication & Certification (Paxos)

In Single-Primary mode, transactions are certified through the Paxos consensus layer before committing on secondary nodes.

Automated Failover & Quorum Sequence

11. Primary Failure Detection

When primary node drops, remaining Group Replication members acknowledge departure via automated membership protocol.

22. Automatic New Primary Election

The secondary instance with highest member_weight and lowest transaction lag is promoted to PRIMARY within <10 seconds.

33. Transparent Router Redirection

MySQL Router detects the cluster state change immediately and redirects port 6446 write traffic without application restarts.

Production Config Blueprint

# MySQL InnoDB Cluster Shell Creation
dba.createCluster('prodCluster', {
  ipWhitelist: '10.0.1.0/24',
  memberWeight: 50,
  consistency: 'AFTER'
});

cluster.addInstance('root@10.0.1.12:3306', {
  recoveryMethod: 'clone'
});
cluster.addInstance('root@10.0.1.13:3306', {
  recoveryMethod: 'clone'
});

# Küme Durumu Kontrolü
cluster.status();

Cluster Health & Triage CLI

mysqlsh root@10.0.1.11:3306 -- cluster status
SELECT * FROM performance_schema.replication_group_members;
SELECT * FROM performance_schema.replication_group_member_stats;

Pros & Strengths

•Official native MySQL solution
•No external consensus daemon required
•Streamlined cluster management via MySQL Shell API

Cons & Constraints

•Minimum 3 node quorum requirement
•Strict requirement for InnoDB tables and primary keys

Pre-Prod Checklist

Every table must have an explicit PRIMARY KEY and use the InnoDB storage engine.
Cluster must consist of at least 3 nodes (odd number recommended to maintain Paxos quorum).
`binlog_format=ROW` and `gtid_mode=ON` must be enabled across all cluster instances.
Deploy at least 2 MySQL Router instances alongside application nodes for router redundancy.

Other HA Topologies

POSTGRESQL

PostgreSQL + Patroni + etcd + HAProxy Enterprise HA

SQLSERVER

SQL Server Always On Availability Groups (AG) Topology

POSTGRESQL

PostgreSQL pgvector HNSW: Production RAG Blueprint & Tuning Guide