ATT MIS VPN and Untangle

Hello All,

I have two untangle units connected to a VPN enabled ATT Managed internet services. The external interfaces on both have an internal 172.16.x.x IP address assigned to them on different subnets. The local internal addresses are 10.0.x.x on a different subnet for each site. I have set routes in order provide site-to-site connectivity. I can ping each untangle device from the other.
However, I am missing how to allow traffic to pass between the local area networks. IE 10.0.1.10 ping 10.0.2.10.

Is there any reason why I shouldn't use OpenVPN and perform a site-to-site? Do I need to set an additional route statement? Is this something where IPSec VPN would come into play? I am a slight noob at interconnecting sites when there is already a private VPN network setup.

I currently have an Untangle v9 and v10.

Thanks for the help!

Andy