Default MTU
The default MTU on the Firewall Threat Defense device is 1500 bytes. This value does not include the 18-22 bytes for the Ethernet header, VLAN tagging, or other overhead.
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Interfaces and Device Settings Regular Firewall Interfaces Configure Advanced Interface Settings About Advanced Interface Configuration About the MTU Default MTU
Last updated: Aug 18, 2025
The default MTU on the Firewall Threat Defense device is 1500 bytes. This value does not include the 18-22 bytes for the Ethernet header, VLAN tagging, or other overhead.