Nokia IPSO 4.0 Reference Manual page 143

Note
If both domain-based VPN and route-based VPN are configured, then domain-based
VPN takes priority. Configuring a VTI does not override the domain-based VPN. The
only way to configure no VPN domain is to create an empty VPN domain group.
3. Create a VPN community and add both gateways to that community.
4. Create a security policy rule and install the policy on both gateways.
Nokia Network Voyager for IPSO 4.0 Reference Guide 143