Home > Workload Solutions > Oracle > Guides > Design Guide — MySQL InnoDB Cluster on Dell EMC PowerStore T > Introduction
MySQL InnoDB Cluster provides a complete high availability solution for MySQL. Each MySQL server instance runs MySQL Group Replication, which provides the mechanism to replicate data within InnoDB Clusters, with built-in failover. MySQL Router can automatically configure itself based on the cluster you deploy, connecting client applications transparently to the server instances. In the event of an unexpected failure of a server instance, the cluster reconfigures itself automatically. In the default single-primary mode, an InnoDB Cluster has a single read-write server instance— the primary. Multiple secondary server instances are replicas of the primary. If the primary fails, a secondary is automatically promoted to the role of primary. MySQL Router detects this change and forwards client applications to the new primary.