Another routing issue - help please

[djay]

Not sure if this is the right place to ask this so apologies if I got it wrong.

I have a pfsense box with 4 interfaces(Just to simplify the question)

WAN
LAN
DMZ
GUEST

I can access DMZ services from the outside i.e coming in from the WAN. No problem with that. 
Outside world > WAN interface > "whatever magic, reverse proxy, etc" > DMZ

I want GUEST to be able to access DMZ services but via the WAN….I hope I am making sense. So
GUEST > as if coming from the outside > WAN interface > "whatever magic, reverse proxy, etc" > DMZ

How do I achieve this please? Any pointer will be great. Thanks all.

[KOM]

What you are describing is called NAT Reflection, but it is a bad idea unless you have no other options.  What is the problem with letting GUEST network access DMZ directly, instead of hair-pinning out and back in again from WAN??

https://doc.pfsense.org/index.php/Why_can't_I_access_forwarded_ports_on_my_WAN_IP_from_my_LAN/OPTx_networks

https://doc.pfsense.org/index.php/Why_does_enabling_NAT_Reflection_break_web_surfing

[djay]

Thank you. I knew I had seen this somewhere but just couldn't remember. Anyway thanks for your help