Once a network has scaled up beyond a single controller capacity, a master/local architecture is recommended.  This allows the master controller to handle configuration and correlation while the locals can be responsible for handling the user traffic.

Steps to Add a local controller to an existing Master:

From the Master GUI:

Configuration -> Network -> Controller -> System Settings

–          Click New Local Controller IPSec Keys

–          Enter the IP Address of the local controller that you are adding

–          Enter an IPSec key

–          Re-Enter the IPSec key

–          Click Add

–          Click Apply (don’t forget)

–          Save Configuration

Or From the Master CLI:

localip <local ip address> ipsec <ipsec key>

From the Local GUI:

Configuration -> Network -> Controller -> System Settings

–          Select Controller Role Drop-Down and select Local

–          Enter the Master Controller IP (VRRP address if using master redundancy)

–          Enter IPSec Key  (Same key you entered on Master)

–          Click Apply

–          Reboot Controller

Or From the Local CLI:

masterip <master ip address> ipsec <ipsec key>