# Assigning Public IP for the DMZ firewall
**URL:** https://forum.networklessons.com/t/assigning-public-ip-for-the-dmz-firewall/54367
**Category:** Routing & Switching
**Created:** [December 23, 2024, 6:53am UTC](https://forum.networklessons.com/t/assigning-public-ip-for-the-dmz-firewall/54367 "2024-12-23T06:53:50Z")
**Posts on this page:** 5
**Page:** 1
### Author:  [@jairaghavan89](https://forum.networklessons.com/u/jairaghavan89)
#### Post date: [December 23, 2024, 6:53am UTC](https://forum.networklessons.com/t/assigning-public-ip-for-the-dmz-firewall/54367/1 "2024-12-23T06:53:50Z")
![S2S VPN]()
Hello all,
I am trying to set up site-to-site VPN between Firewall1 and Azure. For this, I would need to have the same public IP that firewall2 has currently on firewall1. How can I achieve this?
At the moment, I have a clientless VPN enabled on the firewall1 and enabled port forwarding so that I can access the firewall1 WAN facing IP using the Public IP from the internet.
I am new to networking, so kindly guide me in the right path to achieve my goal which is to have S2S VPN between firewall1 and Azure.
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### Author:  [@ReneMolenaar](https://forum.networklessons.com/u/ReneMolenaar)
#### Post date: [December 23, 2024, 10:03am UTC](https://forum.networklessons.com/t/assigning-public-ip-for-the-dmz-firewall/54367/2 "2024-12-23T10:03:17Z")
Hello @jairaghavan89 ,
Each firewall requires a unique public IP address. You can’t have any duplicate IP addresses.
What kind of device is Firewall1? Also, what kind of VPN are you trying to establish? I don’t have any experience with Azure Firewall but I’m guessing this is IPSec with IKEv1 or IKEv2?
Rene
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### Author:  [@jairaghavan89](https://forum.networklessons.com/u/jairaghavan89)
#### Post date: [December 23, 2024, 11:20am UTC](https://forum.networklessons.com/t/assigning-public-ip-for-the-dmz-firewall/54367/3 "2024-12-23T11:20:23Z")
Hello Rene, thanks for the response.
Firewall1 is a Sophos VM inside my lab server. I am anticipating IPSEC IKEv2 implementation between this Sophos and the Azure. And I don’t want to establish site to site from Firewall2 to the Azure.
Is there a way by performing NAT or similar techniques to achieve this, can I achieve this s2s vpn still by the current implementation of port forwarding?
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### Author:  [@ReneMolenaar](https://forum.networklessons.com/u/ReneMolenaar)
#### Post date: [December 23, 2024, 11:29am UTC](https://forum.networklessons.com/t/assigning-public-ip-for-the-dmz-firewall/54367/4 "2024-12-23T11:29:18Z")
Hello @jairaghavan89 ,
Now I see. It is possible to establish IPSec through NAT, but you’ll need a router/firewall that supports NAT-Traversal (NAT-T). I don’t have a tutorial on NAT-T at the moment. I’m not sure what device you use for Firewall2 but see if it supports NAT-T.
Rene
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### Author:  [@jairaghavan89](https://forum.networklessons.com/u/jairaghavan89)
#### Post date: [December 23, 2024, 11:50am UTC](https://forum.networklessons.com/t/assigning-public-ip-for-the-dmz-firewall/54367/5 "2024-12-23T11:50:41Z")
Thanks @ReneMolenaar for the tip. The Firewall2 is a fortigate. Let me study and explore the NAT-T options in it.