L2TP passthrough


Hello, I have a VPN server that is located behind a Balance One and I have forwarded UDP 500, 4500, 1701, AH, and ESP to my VPN server. Nat-t is enabled.

I can’t seem to connect to my VPN server externally. I can connect internally with L2TP and PPTP just fine, I can connect PPTP externally fine, but L2TP does not work externally. I’ve verified my shared keys and everything else.

If I use the built in VPN server, I can connect to the Peplink using L2TP, but that is not great as it is yet another password the user needs to know.

Does anyone have any ideas?


Please open ticket for us to take closer look at the settings of Balance One.

Thank you.


Have you opened the ports in the firewall? Port forwarding won’t happen if the firewall is blocking.


The firewall is set to allow all, so it isn’t blocking anything.

Clifton Hamilton
Operations Manager
Innovative IT Concepts, Inc.


Clifton - not sure we’re saying the same thing. I’m talking about inbound firewall rules, not outbound. If your inbound firewall is truly set to Allow All, that would be a dangerous thing.


Well there is port forwarding and then there is the firewall. By default the firewall in the Peplink is set to allow all. On if we wanted to lockdown traffic incoming or outgoing to an extra level would we change those settings. In short, we are running stock settings.


I have the same exact problem. Did you ever find a solution?


I did, if you have a Pepvpn site-site connection, it uses the same port. Go into the PepVPN and into your VPN connection and inside there is a “data port”, I was recommended to used 32015, but I’m sure any non-conflicting port will be fine.

Clifton Hamilton
Operations Manager
Innovative IT Concepts, Inc.