Ubuntu Server, connected to third-party VPN, cannot be accessed by an external client connected via another VPN

James

7/25/24, 9:18 PM

Setup

Ubiquiti UDM Pro w/Network 7.4.162
- 10.2.2.0/24
Server: Ubuntu 20.04 connected to AirPVN
- eno2 10.2.2.99/32
- eno1 10.2.2.101/32 (enabled temporarily to test if adding a 2nd network connection would help—it doesn't)
- Air VPN setup by importing OpenVPN config file into GUI Settings > Network interface.

$ ip route
default via 10.30.220.1 dev tun0 proto static metric 50
default via 10.2.2.1 dev eno2 proto dhcp metric 100
default via 10.2.2.1 dev eno1 proto dhcp metric 101
10.2.2.0/24 dev eno2 proto kernel scope link src 10.2.2.99 metric 100
10.2.2.0/24 dev eno1 proto kernel scope link src 10.2.2.101 metric 101
10.2.2.1 dev eno2 proto static scope link metric 100
10.30.220.0/24 dev tun0 proto kernel scope link src 10.30.220.26 metric 50
169.254.0.0/16 dev eno2 scope link metric 1000
172.17.0.0/16 dev docker0 proto kernel scope link src 172.17.0.1
172.18.0.0/16 dev br-e8acfbc92281 proto kernel scope link src 172.18.0.1 linkdown
184.75.221.42 via 10.2.2.1 dev eno2 proto static metric 100

Remote WireGuard Client connected to Ubiquiti UDM Pro
- 192.168.3.2/32

Descriptions

The Ubiquiti UDM Pro is my home router.
The Ubuntu Server is at my home, connected to the router.
The Remote WireGuard Client is my laptop connected through the internet.

Problem

When outside my home, connected via my WireGuard VPN, I can access every computer, except the Ubuntu server—if the server is connected to AirVPN. If I drop the AirVPN connection, I can connect to the Ubuntu server just fine.

When the server is connected to AirVPN, Other local computers on the 10.2.2.0/24 network cacn access the server fine. But Remote VPN Connections (laptop) cannot. Pinging from my laptop leads to timeout. Turning off the AirVPN, pings immediately respond.

I've tried adding a 2nd Ethernet connection (10.2.2.101/32), but that didn't help
I've tried Adding explicit firewall rules from 192.168.3.2/32 to 10.2.2.99/32 and 10.2.2.101/32 and 10.30.220.0/24. Did not help.

It feels like Ubuntu is responsible for the blocking, not my router.

Question

Is there a way I can allow my Laptop's WireGuard VPN to connect via my Ubiquiti Router and to my Ubuntu Server, while it is connected to AirVPN? Or is this an intentional mechanic I cannot circumvent?

Thank you.

1 + 3

vpn

networking

openvpn

wireguard

mpboden

7/29/24, 11:49 PM

According to [AirVPN’s website](https://airvpn.org/forums/topic/11432-using-airvpn-with-ubuntu-network-manager/), configuring their VPN via NetworkManager is not recommended: UPDATE 01-SEP-17 Due to multiple, critical problems in network-manager-openvpn which after years have not been solved we recommend to NOT use it. Please understand that we will not provide support to network-manager-openvpn. In GNU/Linux we recommend that you run our free and open source software "AirVPN Suite", "Eddie" or OpenVPN directly

James

7/31/24, 11:57 AM

Thanks. The "Eddie" client is full of ads/popups. Will try via OpenVPN's client.

mpboden

7/31/24, 1:50 PM

Please don’t mark question solved in the title. Instead, add an answer with your solution, and click the check mark to indicate it as the correct answer. This will help others in the future with similar problems.

Score:0

Ubuntu

James

8/2/24, 1:36 PM

There is no answer. It just doesn't work.

+ 0

Elon Musk

I sit in a Tesla and translated this thread with Ai:

EN: Ubuntu Server, connected to third-party VPN, cannot be accessed by an external client connected via another VPN

Post an answer

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