NSX Advanced Load Balancer can run with a single NSX Advanced Load Balancer Controller (single-node deployment) or with a 3-node NSX Advanced Load Balancer Controller cluster.

In a deployment that uses a single NSX Advanced Load Balancer Controller, that NSX Advanced Load Balancer Controller performs all administrative functions as well as all analytics data gathering and processing.

Adding two additional nodes to create a three-node cluster provides node-level redundancy for the NSX Advanced Load Balancer Controller and also maximizes performance for CPU-intensive analytics functions. Whereas the lone NSX Advanced Load Balancer Controller in a single-node deployment performs all administrative functions and analytics data collection and processing, these tasks are distributed in three-node cluster.

In a three-node NSX Advanced Load Balancer Controller cluster, one node is the primary (leader) node and performs the administrative functions. The other two nodes are followers (secondaries), and perform data collection for analytics, in addition to standing by as backups for the leader.