Configuring Inter-VDOM link acceleration with NP4 processors

Configuring Inter-VDOM link acceleration with NP4 processors

FortiGate units with NP4 processors include inter-VDOM links that can be used to accelerate inter-VDOM link traffic.

Traffic is blocked if you enable IPS for traffic passing over inter-VDOM links if that traffic is being offloaded by an NP4 processor.If you disable NP4 offloading traffic will be allowed to flow. You can disable offloading in individual firewall policies by dis- abling auto-asic-offload for those policies. You can also use the following com- mand to disable all IPS offloading

config ips global

set np-accel-mode none set cp-accel-mode none



  • For a FortiGate unit with two NP4 processors there are also two inter-VDOM links, each with two interfaces:
  • npu0-vlink: npu0-vlink0 npu0-vlink1
  • npu1-vlink: npu1-vlink0 npu1-vlink1

These interfaces are visible from the GUI and CLI. For a FortiGate unit with NP4 interfaces, enter the following CLI command (output shown for a FortiGate-5001B):

get hardware npu np4 list














0 On-board   port1 port2 port3 port4
      fabric1 base1 npu0-vlink0 npu0-vlink1
1 On-board   port5 port6 port7 port8
      fabric2 base2 npu1-vlink0 npu1-vlink1

By default the interfaces in each inter-VDOM link are assigned to the root VDOM. To use these interfaces to

accelerate inter-VDOM link traffic, assign each interface in a pair to the VDOMs that you want to offload traffic between. For example, if you have added a VDOM named New-VDOM to a FortiGate unit with NP4 processors, you can go to System > Network > Interfaces and edit the npu0-vlink1 interface and set the Virtual Domain to NewVDOM.

This results in an inter-VDOM link between root and New-VDOM. You can also do this from the CLI:

config system interface edit npu0-vlink1

set vdom New-VDOM


This entry was posted in FortiOS 5.4 Handbook and tagged , , on by .

About Mike

Michael Pruett, CISSP has a wide range of cyber-security and network engineering expertise. The plethora of vendors that resell hardware but have zero engineering knowledge resulting in the wrong hardware or configuration being deployed is a major pet peeve of Michael's. This site was started in an effort to spread information while providing the option of quality consulting services at a much lower price than Fortinet Professional Services. Owns PacketLlama.Com (Fortinet Hardware Sales) and Office Of The CISO, LLC (Cybersecurity consulting firm).

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.