Simple question about client IP

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anahimself
OpenVpn Newbie
Posts: 1
Joined: Fri Feb 02, 2024 11:29 pm

Simple question about client IP

Post by anahimself » Fri Feb 02, 2024 11:37 pm

Hi there,

This might be a dumb question, but I am a bit wondering how and why my client VPN ip is not visible from the lan..

Let me explain, here is the config:

INTERNET => BOX 192.168.1.254 => OPENVPN 192.168.1.250 (vpn client network 10.8.0.0) => Router 192.168.1.251/192.168.0.254 => LAN specific device 192.168.0.100

I only route some specific IP through the vpn (192.168.0.100), and when I am connected I have the client IP 10.8.0.2. So far so good..
I have a route on OpenVPN to use 192.168.1.251 to access 192.168.0.x (instead of default route to internet): route add 192.168.0.100/32 gw 192.168.1.251

I have no masquerading or whatever on openvpn server, but when I try a telnet on http port, the lan device "sees" me as 192.168.1.250 and not 10.8.0.2, any clue why ?

Dump:
197178 IP 192.168.1.250.22394 > 192.168.0.100.http

User avatar
ILoveTravel1
OpenVpn Newbie
Posts: 1
Joined: Sat Feb 03, 2024 2:31 pm

Re: Simple question about client IP

Post by ILoveTravel1 » Sat Feb 03, 2024 2:37 pm

From your provided information, it seems that the issue lies in the visibility of your VPN client IP (10.8.0.2) from the LAN device (192.168.0.100) during a telnet connection on the HTTP port.

A possible reason for the LAN device seeing you as 192.168.1.250 rather than 10.8.0.2 could be due to the absence of proper source address translation for traffic originating from the VPN client network (10.8.0.0) on the OpenVPN server.

To address this, you may want to ensure that your OpenVPN server is configured to correctly handle the source address translation for outgoing traffic from the VPN client network. This involves checking the masquerading or NAT settings on your OpenVPN server.

Additionally, please verify that the routing setup is accurate, especially the route you added on the OpenVPN server (route add 192.168.0.100/32 gw 192.168.1.251) to ensure that traffic is correctly directed to the intended destination.

If the issue persists after checking these configurations, please provide more details about your OpenVPN server setup, such as the specific configuration files and any relevant logs. This will enable a more in-depth analysis and assistance in resolving the matter.

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