What's the right way to share another VPN connection with OpenVPN server?

laflour

Hi,

I'm trying to configure OpenVPN Server in Windows 10 to connect it with another VPN that I have installed (UltraVPN/NordVPN), so all clients use the UltraVPN/NordVPN internet connection.

My current setup:
I have OpenVPN Server installed on Windows 10 (configs are below) and I shared the Windows 10 WIFI internet with OpenVPN Network adapter (network properties, select WIFI Network Adapter -> Sharing -> point to OpenVPN Server network adapter)
In this setup everything works fine - clients can connect to OpenVPN Server, browse the internet, ping the server.

This is my "route print" table for the working connection with WIFI sharing

IPv4 Route Table
===========================================================================
Active Routes:
Network Destination        Netmask          Gateway       Interface  Metric
          0.0.0.0          0.0.0.0      192.168.1.1    192.168.1.145     40
         10.8.0.0    255.255.255.0         On-link          10.8.0.1    281  OpenVPN Server (.1)
         10.8.0.1  255.255.255.255         On-link          10.8.0.1    281
       10.8.0.255  255.255.255.255         On-link          10.8.0.1    281
        127.0.0.0        255.0.0.0         On-link         127.0.0.1    331
        127.0.0.1  255.255.255.255         On-link         127.0.0.1    331
  127.255.255.255  255.255.255.255         On-link         127.0.0.1    331
      192.168.1.0    255.255.255.0         On-link     192.168.1.145    296
    192.168.1.145  255.255.255.255         On-link     192.168.1.145    296
    192.168.1.255  255.255.255.255         On-link     192.168.1.145    296
        224.0.0.0        240.0.0.0         On-link         127.0.0.1    331
        224.0.0.0        240.0.0.0         On-link          10.8.0.1    281
        224.0.0.0        240.0.0.0         On-link     192.168.1.145    296
  255.255.255.255  255.255.255.255         On-link         127.0.0.1    331
  255.255.255.255  255.255.255.255         On-link          10.8.0.1    281
  255.255.255.255  255.255.255.255         On-link     192.168.1.145    296
===========================================================================

Desired State:
I have the UltraVPN/NordVPN installed on my Windows 10, alongside with OpenVPN Server, and I would like to configure my OpenVPN Server to provide the clients with UltraVPN/NordVPN connection, not my local WIFI.
For example, if I establish UltraVPN/NordVPN connection with New Zealand I want my OpenVPN Server to use that connection, not my local WIFI. So the OpenVPN clients are getting the traffic from UltraVPN/NordVPN

Question: How to do it?
I tried to share my UltraVPN/NordVPN network adapter (not WIFI) with OpenVPN Server adapter. In this case, the clients can connect to OpenVPN Server, but they have neither internet, nor they can ping 8.8.8.8.
I checked my OpenVPN Server PC internet and browsed to https://mylocalion.org to confirm that I'm in New Zealand, so the Ultra VPN it's working on server PC, but clients cannot see this traffic.
I reverted back to sharing WIFI connection on OpenVPN Server PC and it's back to normal - but my hometown internet/location, not New Zealand

What I found that when I have WIFI connection shared with OpenVPN Server, and everything is working via WIFI adapter, the moment I establish UltraVPN connection the internet disappears on OpenVPN clients (cannot ping 8.8.8.8), but the connection to OpenVPN Server still successful
The internet on OpenVPN Server PC goes via established UltraVPN and I appear in New Zealand (but not my clients)

There seems to be something wrong with my OpenVPN Server configuration or routing tables.
I captured the routing table when UltraVPN connection is established with the existing WIFI sharing and the table looks like below.
You can see that there is an additional record appears to get 0.0.0.0 to UltraVPN IP address (network adapter IP) somehow cutting off the internet from OpenVPN clients.
But I don't understand why

Could you advise what is wrong and how to configure OpenVPN to get the traffic from another VPN connection?

IPv4 Route Table
===========================================================================
Active Routes:
Network Destination        Netmask          Gateway       Interface  Metric
          0.0.0.0          0.0.0.0      192.168.1.1    192.168.1.145   4265
          0.0.0.0          0.0.0.0         On-link     10.121.228.43      2  UlraVPN
         10.8.0.0    255.255.255.0         On-link          10.8.0.1   4506
         10.8.0.1  255.255.255.255         On-link          10.8.0.1   4506
       10.8.0.255  255.255.255.255         On-link          10.8.0.1   4506
    10.121.228.43  255.255.255.255         On-link     10.121.228.43    257
    85.132.61.122  255.255.255.255      192.168.1.1    192.168.1.145   4266  This is the UltraVPN Public IP
        127.0.0.0        255.0.0.0         On-link         127.0.0.1   4556
        127.0.0.1  255.255.255.255         On-link         127.0.0.1   4556
  127.255.255.255  255.255.255.255         On-link         127.0.0.1   4556
      192.168.1.0    255.255.255.0         On-link     192.168.1.145   4521
    192.168.1.145  255.255.255.255         On-link     192.168.1.145   4521
    192.168.1.255  255.255.255.255         On-link     192.168.1.145   4521
        224.0.0.0        240.0.0.0         On-link         127.0.0.1   4556
        224.0.0.0        240.0.0.0         On-link          10.8.0.1   4506
        224.0.0.0        240.0.0.0         On-link     192.168.1.145   4521
        224.0.0.0        240.0.0.0         On-link     10.121.228.43      2
  255.255.255.255  255.255.255.255         On-link         127.0.0.1   4556
  255.255.255.255  255.255.255.255         On-link          10.8.0.1   4506
  255.255.255.255  255.255.255.255         On-link     192.168.1.145   4521
  255.255.255.255  255.255.255.255         On-link     10.121.228.43    257
===========================================================================

port 1194
proto udp
dev tun

ca "C:\\Program Files\\OpenVPN\\config\\ca.crt"
cert "C:\\Program Files\\OpenVPN\\config\\server.crt"
key "C:\\Program Files\\OpenVPN\\config\\server.key"
dh "C:\\Program Files\\OpenVPN\\config\\dh2048.pem"

topology subnet
server 10.8.0.0 255.255.255.0
push "redirect-gateway def1"
client-to-client
duplicate-cn

keepalive 10 120
cipher AES-256-CBC
max-clients 10
persist-key
persist-tun
log
openvpn.log
verb 4
explicit-exit-notify 1

client
dev tun
proto udp
remote <myserverIP> 1194
resolv-retry infinite
keepalive 5 10
nobind
persist-key
persist-tun
verb 4
ca ca.crt
cert Client1.crt
key Client1.key[/olog]

TinCanTech

laflour wrote I'm trying to configure OpenVPN Server in Windows 10 to connect it with another VPN that I have installed (UltraVPN/NordVPN), so all clients use the UltraVPN/NordVPN internet connection.

Windows cannot do this.

laflour

ok, so if I install it on Ubuntu, what would be the right configuration to apply then?

TinCanTech

It is not something which openvpn can configure. You need to use policy based routing.

https://community.openvpn.net/openvpn/wiki/Concepts-PolicyRouting-Linux

laflour

Are there any other options to explore for Windows? Like bridging between networks or maybe using the second PC where the UltraVPN be used and connect to it as the interim service (but then I assume I need to figure out how to do port forwarding so the request reaches my VPN server)?

TinCanTech

laflour wrote Are there any other options to explore for Windows?

Nope .. but you are free to dig yourself into a hole ..

300000

you can do this on windows what you need is make two openvpn network card and make connection one act as openvpn server and the second act as openvpn client connect to vpn service provider , now what you want is from internet your openvpn client connect to your openvpn server at home and have some connection over your vpn service provider ?

why do you want your client openvpn connection go though vpn provider and connect to your home ? maybe you need some thing at home or what?

it is more easy to make it work on windows server than windows home edition but it will work.

TinCanTech

When the Windows server+client connects to Nord, all clients connected to the Windows server will be dropped except for clients within your home network. But you don't need two network cards to do that either.

300000

if you like I can help you set up the way you like I have set up the same you like and it work ok my set up as

my main computer run windows server 2012 and install both openvpn client and openvpn server at the same time

openvpn client connect to freeopenvpn service to test and my ip address change to their so everything working.
my openvpn server run on the same computer and I use my android phone connect to my openvpn server on 4g network at home while my computer connected to freevpn service at the same time

my android phone can go to internet and use as nomal and my android phone have change its ip address as freevnp service as should be and my android phone can connect only to openvpn server computer at the same time .

I don't have time at the moment to make it so my android phone can only connect to my computer at home now, dicking on routing will make it find the way to connect to every host on lan at the openvpn server at home . but it works as suck ok