How Cluster Redundancy Works
The following simplified scenario describes how cluster redundancy works and how managed APs fail over from one controller cluster to another.
- After you enable and configure cluster redundancy on the controller, managed APs will obtain IPs of all nodes in Active cluster as server list, and all IPs of all nodes in Standby cluster as failover list, which is shown in AP as:
{"Server List":[ "IP_A1", "IP_A2, "IP_A3", "IP_A4"], "Failover List":["IP_B1", "IP_B2, "IP_B3", "IP_B4"]}.
- If Cluster A goes out of service or becomes unavailable, APs managed by Cluster A will attempt to connect to the IP addresses (one node at a time) specified for Cluster A.
- If managed APs are unable to connect to the IP addresses specified for Cluster A, they will attempt to connect to the IP addresses (one node at a time) specified for Cluster B.
- If managed APs are able to connect to one of the IP address specified for Cluster B, they fail over to Cluster B. APs will move to the zone it belongs to when failover.
NOTE
The standby cluster to which APs fail over must have sufficient license seats to accommodate the new APs that it will be managing. If Standby cluster has insufficient license seats, some APs are unable to get HA license, so can only stay in staging zone in Standby cluster.