# config system interface
edit ipsec-tunnel-1
set mtu-override enable/disable
set mtu 1400
end
end
"By default, the MTU of an IPsec VPN Interface is dynamically calculated."
Technically, how does it calculate the MTU?
Hello Andy,
MTU is calculated based on multiple factors - parent interface, FortiOS versions, algorithm used, if NAT-T is used or not, etc.
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