VPN IP vs External IP Usage within IPFire Network/DMZ

VPNs OpenVPN
1

I configured some adminstrative pages on my DMZ server to be accessed only by some internal Green/Blue IPs or a configured OpenVPN network IP.

After connecting via roadwarrior to iPFire, I have - aside of the assigned WLAN IP which is then NATted to an external IP - an OpenVPN IP via tun0.

But it appears that when accessing my server in the DMZ just the external ip is shown in the logs but not the assigned OpenVPN IP.

As a result, I cannot access these restricted pages via roadwarrior connection from abroad.

I wonder if someone please could explain me how to let my client show/use the assigned OpenVPN roadwarrior IP within the iPFire network when connected.

Client is running kubuntu 26.04.1

2

:thinking: Does your WLAN network use IPv6?

3

Hi, no, the WLAN IP is a 10.0.0.x IPv4 address and the external IP it becomes natted to is v4 as well.

Edit: it appears there is assigned IPv6 in the WLAN, too. So both v4 and v6

4

This is not a problem with iPFire, rather it’s caused by setting real IP in my web server config in the orange DMZ.. This results in getting the roadwarrior OpenVPN IP stripped as well and that’s finally the cause why I cannot access these administrative pages.

I must investigate how to exclude the OpenVPN IP from this - however I’ll close this one, thank you.

Edit: I applied strikethrough as this above was an incorrect guess.

5

Could you run a simple test?

Disable IPv6 on Kubuntu and reboot the system.
After rebooting, check the OpenVPN connection again.

Regards

6

Hi, I temporarily disabled IPv6 but that didn’t help. But I was hinted by ChatGPT towards the solution: I didn’t enter the IPFire OpenVPN x.x.x.1 IP as DNS1 as part of the roadwarrior config; so when resolving www.mydomain.com just the external internet IP has been returned. After adding this DNS1 entry, the hostname is now resolved correctly to the local DMZ address and the web server behaves as planned and configured.