Chapter 9 High Availability for FortiOS 5.0 : Configuring and connecting HA clusters : Example: adding a new unit to an operating cluster
  
Example: adding a new unit to an operating cluster
This procedure describes how to add a new FortiGate unit to a functioning cluster. Adding a new unit to a cluster does not interrupt the operation of the cluster unless you have to change how the cluster is connected to the network to accommodate the new cluster unit.
You can use this procedure to add as many units as required to the cluster.
To add a new unit to a functioning cluster
1. Install the same firmware build on the new cluster unit as is running on the cluster.
2. Configure the new cluster unit for HA operation with the same HA configuration as the other units in the cluster.
3. If the cluster is running in Transparent mode, change the operating mode of the new cluster unit to Transparent mode.
4. Connect the new cluster unit to the cluster.
5. For example, for a configuration similar to the FortiGate-620B cluster configuration described in this chapter, see “To connect the cluster to the network”.
6. Power on the new cluster unit.
When the unit starts it negotiates to join the cluster. After it joins the cluster, the cluster synchronizes the new unit configuration with the configuration of the primary unit.
You can add a new unit to a functioning cluster at any time. The new cluster unit must:
Have the same hardware configuration as the cluster units. Including the same hard disk configuration and the same AMC cards installed in the same slots.
Have the same firmware build as the cluster.
Be set to the same operating mode (NAT or Transparent) as the cluster.
Be operating in single VDOM mode.