OpenVPN Support Forum

Hi OpenVPN Experts -

Although I have only a basic knowledge of networking and this is my first use of OpenVPN Connect, I was able to use advice I found here from TinCanTech to create an OVPN config file with inline certs and keys, load it to the latest OpenVPN Connect on my iPad, and connect to my R7000 with external static IP. The connection seems healthy and I have traffic. So I already owe thanks to this forum.

I want to connect to resources on the host LAN. Only one thing between me and success: I'm not getting an IP. I have a private IP: 192.168.254.2. How can I force DHCP, or even set a static IP? I can post my config and/or log if it would help.

Many thanks in advance -
JBusch

jbusch223@gmail.com wrote: ↑

Sat Jun 19, 2021 9:05 pm

I'm not getting an IP

In what sense ? You've lost me ..

Edit: You mean, you are not getting a 192.168.. address ?

If so then you need to setup your server to allow access to the LAN.

Sorry, not clear enough. When my iPad is connected to the host R7000 by OpenVPN, OpenVPN reports the iPad's IP address as 192.168.254.2. The R7000 is the DHCP server on the host network, and it is assigning IPs in 192.168.2.xxx. I want the iPad to have an IP in that range so I can see and connect to devices on that network. I was hoping that the R7000 would assign a 192.168.2.xxx IP, but it's not happening. Hope this helps. Reading that I may have to set up my server to allow access to the LAN, I can say that I am using OpenVPN on a Windows10 machine to connect to the same host, and getting a 192.168.2.xxx IP, so it works the way I expected in that environment. Please let me know what else I can do to help. Thanks again!

That's not how it works and your iOS cannot have an IP address on your LAN.

You need to use routing on the server device.

Hello jbusch223@gmail.com,

Just as TinCanTech explained, that is not how it works. But allow me to add just a bit more explanation.

VPN works with a completely separate virtual network. It's a network that exists only within the VPN software, on the VPN server and the VPN client(s). And it's in a private IP range. That makes it a Virtual Private Network, or VPN. To avoid IP routing conflicts, this subnet must be different from the one you are already using. So if you are using 192.168.2.* on your Netgear router, then the VPN server software on the Netgear router should definitely not be using that range too. That is why it assign a different range entirely.

How can you communicate to 192.168.2.* subnet from the VPN subnet? That's done through routing. Packets sent from the VPN subnet to the 192.168.2.* subnet will reach the VPN server software's address, which functions as a gateway, and which will then forward it to the correct 192.168.2.* subnet. And packets sent from the 192.168.2.* subnet to the VPN subnet, will reach the router's gateway address and then forward it to the VPN subnet.

I hope that helps to understand the concept.

Kind regards,
Johan

This diagram might help here:
https://community.openvpn.net/openvpn/w ... gConflicts

Hi Johan -

Thanks for your explanation. I understand (barely) the routing concept shown in the diagram. My client side subnet is 192.1688.1.x, and my server side subnet is 192.168.2.x. As mentioned earlier, I am connecting successfully with TUN and have traffic. Paragraph three of your explanation makes it sound as if the routing on the NetGear that will give me access to the server side subnet happens without setup on my part. Not true?

I'm happy to learn more and to do any setup necessary. My practical goal is to connect to SMB shares on 192.168.2.x using Files. In fact, I am only interested in accessing shares on a single device with a static IP on the server side subnet. Please let me know my next step.

Many thanks again -
JBusch

Hello JBusch,

I would expect that if the Netgear R7000 router runs an OpenVPN server, that it will handle the routing in such a way that VPN clients can access IP addresses that this router manages for the local network. But now we are talking about an OpenVPN open source community edition server setup on a third-party router. I will therefore move this ticket to the community section of the forums. Support may also be available from Netgear, since this is a Netgear device.

Kind regards,
Johan