Windows 10 SplitTunneling - Internet Not Working

I have added Set-VpnConnection -Name "TEST" -SplitTunneling $True -PassThru -ThirdPartyVpn to enable split tunnelling so that I can connect to VPN and use internet connection simultaneously. Below are the results

Name                  : TEST
ServerAddress         : https://test.test.com
Guid                  : {50DD97B3-E0F3-12ED-9F42-BE66495E28C5}
ConnectionStatus      : Disconnected
RememberCredential    : True
SplitTunneling        : True
DnsSuffix             : 
IdleDisconnectSeconds : 0
PlugInApplicationID   : FortinetInc.FortiClient_45ggfgfgfj
CustomConfiguration   : #document

However, I am not able to connect to the internet even though SplitTunneling is enabled. How can I resolve the issue?

VPN split tunneling doesn't work

Within the VPN client you configure split tunneling and the split tunneling does not work.

You could experience this issue if. . .

1. The VPN server side you connect does not allow split tunneling and routes are pushed to the clients upon each connection

2. Per VPN server policies, network access policies, or VPN client settings, it could monitor for changes in the active VPN session routing table and if a change occurs . .

   • it could push the routes back to the client overwriting your modifications
   • it could disconnect the VPN session and force you to reconnect and upon connection the new routes with lower metric, etc. are pushed to the VPN client again

Potential Solution

If you do not personally administer the VPN server and you cannot get split tunneling to work, static routes to stick, or refrain the client from disconnecting when static routes are changed, then reach out to the VPN\Server admin and ask about this functionality.

Maybe this is prohibited for a security reason or maybe you are the first to ask about it and it'll be considered for further research and potentially available in the future to use.

fortinet

Controlling how routing changes affect active sessions

Dynamic routing changes can occur while a FortiGate is processing traffic. Routing changes that affect the routes being used for current sessions, may affect how the FortiGate continues to process the session.You can control how active sessions are affected when dynamic routing changes occur that affects the routes the active sessions are using.

You can configure whether the FortiGate maintains the original routing for the sessions that are using the affected routes, or applies the routing table changes to the active sessions, which may cause destinations to change.

To configure how dynamic routing changes affect active sessions - CLI:

config system interface

  edit <interface_name>

    set preserve-session-route {enable | disable}

  next

where you set the following variables:

CLI Option: <interface_name>

• Description: The name of the interface where you want to configure how dynamic routing changes affect active sessions running through it.

CLI Option: enable

• Description: All sessions passing through the interface when the routing changes occur, are allowed to finish and aren't affected by the routing changes.

CLI Option: disable (default)

• Description: When a routing change occurs, the new routing table is applied to the active sessions passing through the interface. The routing changes may cause the destinations of the sessions to change.

Source