How to destination NAT a secondary IP address

Forum|Forum|1 year ago
September 9, 2025
1 reply
429 views

Hi,
I am considering using destination NAT on the secondary IP address of the internet-facing port to build a DMZ network.

Although I were able to configure destination NAT for the secondary IP address, but it is not working.

My hypothesis is that the product's specifications might prevent a secondary IP address from being used for destination NAT.
I appreciate any advice from someone with knowledge on this.

Thanks,
Kenji

FortiGate

Best answer by funkylicious

hi,

if the secondary IP is from a different network than your main/primary wan that is routed by your ISP is most likely not routed by them, you should confirm with them.

there should be no issues with using secondary IP ( not necessary though to have it as set secondary, as long that the subnet/ip is routed correctly - just use it as VIP ) for DNAT/VIP .

funkyliciousAnswer

SuperUser

hi,

if the secondary IP is from a different network than your main/primary wan that is routed by your ISP is most likely not routed by them, you should confirm with them.

there should be no issues with using secondary IP ( not necessary though to have it as set secondary, as long that the subnet/ip is routed correctly - just use it as VIP ) for DNAT/VIP .

"jack of all trades, master of none"

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