Multiple & Simultaneous Connections from OpenVPN Client

[jay.balla]

Hi Guys,

I have two different OpenVPN networks and many times I need to work on both the environments simultaneously. Switching to the networks each time and connecting the servers back is being painful for me. Is there any what I can connect to both the networks at a time?

Best Regards,
Jay.

[novaflash]

Yeah, clients based on the open source version can connect multiple networks at the same time. It requires that you have a TAP adapter for each active VPN tunnel. By default only one is installed. Programs that allow multiple connections will either manage this automatically (like on Linux and Mac) or you'll have to add one manually using tools provided with the program or a settings screen where these can be added. You can use for example OpenVPN GUI or TunXTen or Viscosity or... well there's a whole list. Personally I like TunXTen to manage shitloads of connections easily. It has a settings screen where you can add more TAP adapters as needed.

Always make sure that no more than one server has full-tunnel redirection enabled (or none at all), and that none of the subnets you want to access simultaneously interfere with each other. Basically don't have the same subnet twice.

[novaflash]

Forgot to mention;

The OpenVPN Connect Client does not support having multiple networks connected at the same time on purpose. It's meant for end-users that need just one connection. This is to avoid people running into subnet collissions and routing problems and unexpected paths of traffic. Only a system administrator would know how to deal with this and those can use the more advanced clients out there.

[jay.balla]

Thank you NovaFlash for your immediate reply. I will try creating TAP adapters and check. Ours are not different subnets but different networks. So, I hope, there will be no such conflicts.

[novaflash]

Different physical networks that have the same subnets (192.168.0.0/24 on both networks for example) will cause a subnet collission.

Edit: when both connected at the same time from a single computer.

[jay.balla]

Hi NovaFlash,

I tried to change the IP address on TAP adapter by following below in red. But my VPN got disconnected.

Go to Start -> Control Panel -> Network Connections.
You should see a "TAP-Windows Adapter" with a name like "Local Area Connection 3". Right click and rename this to something shorter and without embedded spaces such as "my-tap".
Now right click again and select properties.
Select Internet Protocol (TCP/IP) from the list and click on "Properties".
Set the IP address and subnet mask of your new TAP device. For the example below we will use an IP of 10.3.0.1 and a subnet mask of 255.255.255.0. Other fields can be left as they are.

As I said, we have two different VPNs. One is in 10. network and other one is in 172. network. As per my understanding, I need to add one TAP adapters for each. I'm not sure what IP I need to give.

Could you please let me know how exactly I need to proceed?

[novaflash]

I have no idea why you're setting an IP address on your TAP adapter. Normally you do not do that. You simply connect to both servers. The TAP adapters are assigned IP addresses automatically by the VPN server.

[jay.balla]

My goal is to use two different VPNs at a time. When I connect to VPN-A, I see that TAP Adapter gets enabled. When I need to connect to VPN-B, I need to disconnect VPN-A (then TAP Adapter gets disabled) and connect to VPN-B. Then the same TAP Adapter gets enabled. In both the cases, I'm able to connect only one VPN at a time.

My understanding is, I need to create two TAP adapters for both the VPNs to make the simultaneous connections. Please correct me if I'm wrong.

[TinCanTech]

Are you using OpenVPN-AccessServer(Licensed product) or OpenVPN-CommunityEdition(Free software)

[novaflash]

Hello jay.balla,

I already gave you the answers you need. Did you install any of the other clients yet?

[jay.balla]

It is free version. What I'm using is the client openvpn-connect-1.8.3.

[novaflash]

If you had read what I posted, you would now not be using the OpenVPN Connect Client. Kindly read carefully and try again, but with the correct client this time.

[siliconrockstar]

@novaflash - what are some of the more advanced clients that can handle multiple connections?

[novaflash]

Yeah, clients based on the open source version can connect multiple networks at the same time. It requires that you have a TAP adapter for each active VPN tunnel. By default only one is installed. Programs that allow multiple connections will either manage this automatically (like on Linux and Mac) or you'll have to add one manually using tools provided with the program or a settings screen where these can be added. You can use for example OpenVPN GUI or TunXTen or Viscosity or... well there's a whole list. Personally I like TunXTen to manage shitloads of connections easily. It has a settings screen where you can add more TAP adapters as needed.

Always make sure that no more than one server has full-tunnel redirection enabled (or none at all), and that none of the subnets you want to access simultaneously interfere with each other. Basically don't have the same subnet twice.