FGSP basic peer setup

The FortiGate Session Life Support Protocol (FGSP) is a proprietary HA solution for only sharing sessions between entities based on peer-to-peer communications. The entities could be standalone FortiGates or an FGCP cluster. This example uses two peer FortiGates. The load balancer is configured to send all sessions to Peer_1, and if Peer_1 fails, all traffic is sent to Peer_2.

To configure a basic FGSP peer setup:

These instructions assume that all FortiGates have been factory reset.

1. Make all the necessary connections as shown in the topology diagram.
2. On Peer_1, configure the peer IP in which this device will peer with:

   config system cluster-sync
       edit 1
           set peerip 10.10.10.2
       next
   end
   

   If there are multiple peer IPs from the same peer, enter them as separate entries. If there are multiple peers, enter the IP of each peer in separate entries.

   Sessions by default will be synchronized over layer 3 on the interface in which the current unit connects to the peer's IP.

3. On Peer_2, configure session synchronization:

   config system cluster-sync
       edit 1
           set peerip 10.10.10.1
       next
   end

4. Configure identical firewall policies on each peer, such as for traffic going from the same incoming interface (port1) to the outgoing interface (port2).
   

To test the FGSP peer setup:

1. Initiate TCP traffic (like HTTP access) to go through Peer_1.
2. Check the session information:

   # diagnose sys session filter src <IP_address>

   # diagnose sys session list

3. Enter the same commands on Peer_2 to verify if the same session information appears.

Optional filters

Filters can be added to synchronize certain types of sessions that meet the filter criteria.

To add filters for session synchronization:

config system cluster-sync
    edit <id>
        config session-sync-filter
            set srcintf <interface>
            set dstintf <interface>
            set srcaddr <IPv4_address>
            set dstaddr <IPv4_address>
            set srcaddr6 <IPv6_address>
            set dstaddr6 <IPv6_address>
        end
    next
end

Filter examples

To synchronize only sessions with a particular source subnet:

config system cluster-sync
    edit 1
        config session-sync-filter
            set srcaddr 192.168.20.0/24
        end
    next
end

To synchronize only sessions with a particular source address range:

config system cluster-sync
    edit 1
        config session-sync-filter
            set srcaddr 192.168.20.10 192.168.20.20
        end
    next
end

To synchronize only sessions with a particular destination address range:

config system cluster-sync
    edit 1
        config session-sync-filter
            set dstaddr6 2001:db8:0:2::/64
        end
    next
end

Session pickup

You can enable this setting to synchronize connectionless (UDP and ICMP) sessions, expectation sessions, and NAT sessions. If session pickup is not enabled, the FGSP does not share session tables for the particular session type, and sessions do not resume after a failover.

To enable UDP and ICMP session synchronization:

config system ha
    set session-pickup enable
    set session-pickup-connectionless enable
end

Session synchronization

You can specify interfaces used to synchronize sessions in L2 instead of L3 using the session-sync-dev setting. For more information about using session synchronization, see Session synchronization interfaces in FGSP.

To configure session synchronization over redundant L2 connections:

config system standalone-cluster
    set session-sync-dev <interface 1> [<interface 2>] ... [<interface n>]
end

VDOM synchronization

When multi-VDOM mode is enabled, you can specify the peer VDOM and the synchronized VDOMs. The peer VDOM contains the session synchronization link interface on the peer unit. The synchronized VDOMs' sessions are synchronized using this session synchronization configuration.

To synchronize between VDOMs:

config system cluster-sync
    edit 1
        set peerip <IP address> 
        set peervd <vdom>
        set syncvd <vdom 1> [<vdom 2>] ... [<vdom n>]
    next
end