PFCP load balancing

FortiGate 6000F includes support for load balancing the Packet Forwarding Control Protocol (PFCP). PFCP is an addition to 3GPP that provides 4G Control plane and User Plane Separation (CUPS) and 5G signaling evolution. When PFCP is used as the control plane, the user plane employs GTP-U encapsulation. PFCP takes many of the roles that are provided by GTP-C in 3G/4G networks and provides session awareness and tracking of GTP-U user plane traffic while also providing control plane initiation.

FortiGate 6000F PFCP support includes supporting PFCP session synchronization for FGCP HA.

You can use the following command to enable or disable FortiGate 6000F PFCP load balancing.

config load-balance setting

set pfcp-load-balance {disable | enable}

end

The following flow rule is also available to direct PFCP control plane traffic to the primary FPC.

edit 21

set status disable

set vlan 0

set ether-type ipv4

set src-addr-ipv4 0.0.0.0 0.0.0.0

set dst-addr-ipv4 0.0.0.0 0.0.0.0

set protocol udp

set src-l4port 0-0

set dst-l4port 8805-8805

set action forward

set forward-slot master

set priority 5

set comment "pfcp to primary blade"

end

By default, both of these configurations are disabled and PFCP control plane and user plane traffic is not load balanced. The DP sends all PFCP control plane and user plane traffic to the primary FPC.

To load balance PFCP user plane traffic to multiple FPCs, you can set pfcp-load-balance to enable. This also enables the PFCP flow rule. PFCP user plane traffic is then load balanced across all FPCs while PFCP control plane traffic is still handled by the primary FPC. This is the recommended configuration for load balancing PFCP traffic.