IKE monitor for FGSP

Split-brain situations occur in a scenario where session synchronization is down between two FGSP peers. This can have an effect if IKE fails over from one unit to another, causing the tunnel to be invalid due to the IKE session and role being out of sync, and ESP anti-replay detection. In split-brain situations, the IKE monitor provides a mechanism to maintain the integrity of the state tables and primary/secondary roles for each VPN gateway. It continues to provide fault tolerance by keeping track of the timestamp of the latest received traffic, and it uses the ESP sequence number jump ahead value to preserve the sequence number per gateway. Once the link is up, the cluster resolves the role and synchronizes the session and IKE data. During this process, if the IKE fails over from one unit to another, the tunnel will remain valid and traffic continues to flow.


The IKE monitor only works with 2 peers in FGSP.

To configure the IKE monitor:
config system cluster-sync
    edit <id>
        set peerip <address>
        set ike-monitor {enable | disable}
        set ike-monitor-interval <integer>
        set ike-heartbeat-interval <integer>
        set ike-seqjump-speed <integer>

ike-monitor {enable | disable}

Enable/disable IKE HA monitor (default = disable).

ike-monitor-interval <integer>

Set the monitoring interval for determining how fast the cluster members detect split-brain mode, in seconds (10 - 300, default = 15).

ike-heartbeat-interval <integer>