Chapter 9 High Availability : FortiOS 5.2 HA new features : FortiOS 5.2 HA new features
  
FortiOS 5.2 HA new features
New FortiOS 5.2 HA features are described in the following sections:
Temporarily selecting a cluster unit to be the primary unit, “Temporarily setting a cluster unit to be the primary unit”
DHCP and PPPoE supported for HA clusters, “FortiGate HA compatibility with DHCP and PPPoE”.
IPv6 Management Interface Gateway, “Configuring the reserved management interface and SNMP remote management of individual cluster units”
IKEv2 Message ID synchronization and failover support, “Synchronizing SAs for IKEv2”
Synchronizing GTP Tunnel sessions and GTP tunnel failover support, “Synchronizing GTP sessions to support GTP tunnel failover”
New VRRP features “VRRP Groups” and “Using a Second Destination IP (VRDST)”