SoftEther VPN User Forum

I'm trying to relocate VPN from existing server (1) version 4.22 running on Win10 to a new server (2) version 4.38 running on Server 2016, the settings on the servers are the same. including L2TP, Virtual NAT & DHCP.

I'm using port forwarding for TCP 433, and UDP 500, 4500 & 1701 on the router to an internal IP address, and use the same IP address for both machines; clearly, only one can be active at a time.

Server 1 has been in use for years, server 2 is being set up.

I'm able to connect to server (1) from Win10 using native VPN connection and SoftEther client, also from Android using L2TP.

When I connect to server (2) from Win10, from outside the local LAN, the connection laches, a local IP address is assigned as shown in the log, but that IP address does not show up in the Win10 (client) ipconfig listing and there is no access to the remote LAN PCs.

I went through testing this several times.

Any ideas as to what might be happening?

david@rabboar.com wrote: ↑

Mon Jan 24, 2022 8:01 pm

...and use the same IP address for both machines; clearly, only one can be active at a time.

Clearly indeed but did you reboot router/switch after the change to update MAC address on the LAN?

Also, can you access server 2 from Android or using native VPN connection?

1. I do not reboot the router, but it's mapping is OK, or else I'd not be able to communicate with server 2, as I said, the connection works all the way to assigning a local IP address.

2. I can connect from Win10 using built in VPN or Softether client, I did not check for Android connection.

I was wondering if the issue is a DHCP address collision, as I have SuperNAT and DHCP on both servers.

I have another DHCP server on the LAN, do I need SuperNAT and DHCP to allow for L2TP connections?

David L.

david@rabboar.com wrote: ↑

Tue Jan 25, 2022 2:09 pm

I have another DHCP server on the LAN, do I need SuperNAT and DHCP to allow for L2TP connections?

To use DHCP server on the LAN, bridge it and disable SNAT, regardless of L2TP or any other VPN protocol.

If you believe that "IP assignment fails to propagate" then switch to a static IP on the client, for a test, and check connectivity.