Troubleshooting Cisco APIC Cluster

Troubleshooting Cisco APIC Cluster

Cisco APIC is deployed in a cluster with a minimum of three controllers. The ultimate size of the controller cluster is directly proportionate to the size of the Cisco ACI deployment and is based on transaction-rate requirements. Any controller in the cluster can service any user for any operation, and a controller can be transparently added to or removed from the cluster. APICs form a cluster and talk to each other using the infra network provided by leaf and spine.

The APIC cluster uses a large database technology called sharding. The APIC configuration database is partitioned into logically bounded subsets, called shards, and each shard has three replicas. The shards are evenly distributed across the APICs, while the shard data assignments are based on a predetermined hash function, and a static shard layout determines the assignment of shards to appliances. This specific database technology provides scalability and reliability to the data sets that are generated and processed by the Cisco APIC.