L2TP and manual configuration

marcdeblanck

when I try to connect to the vpn service the manual setup of the client side gets ignored and I receive a DHCP address

shiprasahu93

Hello @marcdeblanck,

Do you mean that the L2TP adapter of the client is assigned with the DHCP address assigned by DHCP server on LAN and not the L2TP IP Pool configured on the firewall?

Also, are you seeing issues like not able to connect to the right resources or access to internet?

Could you please refer to the KB below and make sure that it is configured as per the link below?

https://www.sonicwall.com/support/knowledge-base/l2tp-vpn-configuration/170504819998260/

Thanks!

Stay safe!!

[Deleted User]

Hi @marcdeblanck ,

Was this issue ever resolved?

marcdeblanck

nope, the vpn connection works but I need to be able to connect to the client, so it has to get the same ip address on the vpn every time

now it gets a random ip from the l2tp connection even when i set the client to use a fixed ip

shiprasahu93

We cannot assign static DHCP entries to L2TP clients as we can with GVC clients. If you have just a single L2TP client, you can reduce the L2TP IP Pool to that specific IP and you should always get that IP address on the client. Otherwise, SonicWall will assign one of the IP addresses from the L2TP IP Pool.

I would also like to add that the L2TP VPN is for remote access from client side to remote resources on the firewall. The connectivity on the other way around may not always work. It is more of an unidirectional connection.

Thanks!

Saravanan

Hi @MARCDEBLANCK,

Unfortunately, the static assignment of IP address to the L2TP client is not available. The technical reason behind this is, "the L2TP VPN adapter on the client PC will not produce a Physical / Ethernet / MAC address which can be then mapped to a desired IP address on the SonicWall appliance".

With GVC, this requirement can be achieved due to the fact that GVC adapter contains a MAC address when GVC software is installed. In the SonicWall, we can map the IP address along with corresponding MAC address and the desired IP can be leased out to the VPN user. So, typically both L2TP VPN and SSL VPN doesnt support this static IP usage for now because of the above technical reason.

The below KB article can give you an overview of how the static IP is mapped to a MAC in case of GVC users.

https://www.sonicwall.com/support/knowledge-base/how-to-configure-static-dhcp-assignments-for-the-gvc-virtual-adapter/170505982918449/

Hope the reason behind the scene helps.

Have a good one!!!