RFC1918 addresses inbound to untrust interface

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RFC1918 addresses inbound to untrust interface

L3 Networker

I have a pair of palos in azure, they are frontheaded by a LB. I also have a VPN gateway in the gateway subnet of the vnet where these components live. Not ideal but I am trying to connect a legacy vWAN hub to a new landing zone. I have a VPN from old to new using VNGs. I have a no-net from new landing zone vnets from trust to untrust so the rfc1918s head outbound without being transformed to public NAT address. But would the untrust interface just drop them anyway knowing they are RFC1918? What about when my RFC1918 from legacy vWAN come inbound to the untrust and try to route to trust? Wouldn't the untrust interface drop those also? Is there a method to to get rfc1918 traffic inbound to the untrust and forward to trust?


Cyber Elite
Cyber Elite

Hi @S_Williams901 ,


I am not certain what you are asking, but I have a customer with a VM-Series in Azure.  He has RFC1918 IP addresses on the untrust interface, and it works fine.  Azure is doing the NAT.





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I see the rfc1918 in the VNG tunnel but never see it get to the untrust interface....

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