HA feature overview
FortiDDoS appliances can be deployed as standalone appliances or as members of a high availability (HA) cluster. A cluster is two or more nodes. A node is an instance of the appliance/system. In a cluster, one node is the primary node, also called the master node. The other members of the cluster are secondary nodes, also called slave nodes.
HA solutions depend on two types of communication among cluster members:
• Heartbeats. A cluster node indicates to other nodes in the cluster that it is up and available. The absence of heartbeat traffic indicates the node is not up and is unavailable.
• Synchronization. During initialization, the primary node pushes its configuration (with noted exceptions) to member nodes.
FortiDDoS supports
active-passive clusters.
Figure 144 shows an active-passive deployment. In an active-passive deployment, the primary node is the active node that handles all traffic. In the event that the primary node goes offline due to hardware failure or system maintenance,
failover takes place. In failover, the standby node becomes the primary node and processes the traffic that is forwarded along the network path.
In an active-passive cluster, only the management IP address for the primary node is active. You can log into the user interface via a remote HTTP or SSH connection only when it has primary node status and its IP address is active. To access the user interface of an appliance in standby status (the active-passive slave), you must use a console port connection.
