Comprehensive and Detailed Explanation From Exact Extract documents and Knowledge:

To scale performance beyond a single unit, Fortinet provides two primary clustering and synchronization methods:

FGCP Active-Active: This mode distributes network traffic among all members of the cluster, allowing the combined processing power of multiple units to handle higher throughput and security inspection loads.

FGSP (FortiGate Session Life Support Protocol): This protocol is used to synchronize session information between independent FortiGate units or clusters. It is commonly used in large-scale environments where external load balancers distribute traffic across multiple FortiGates, ensuring that if traffic for a session is asymmetric (sent to one unit but returned to another), the return unit has the necessary session state to allow the traffic. In contrast, FGCP Active-Passive provides redundancy but does not scale performance as the secondary unit remains idle.

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