Connecting two virtual networks with site-to-site connection

We have created a Service Mode Classic VPN named CloudMakersClassic in order to access to VPNs. We have created another VPN in an ARM Virtual Network called CloudMakers to take advantage of the resource templates and resource groups. The two virtual networks are different by features and by roles, one being the VN for frontend servers and one for backend servers. Up to now, they don't communicate with each other. Up to now, they are two unrelated networks that could communicate only with public IP (but in our sample only ARM VN has one) and without any special privilege. In this situation we can have some security issues, that we need to avoid. So, we can configure a site-to-site connection to allow a privileged access to the classic VN. So, we can configure a site-to-site connection to allow access to the classic VN.

To start, we need to configure CloudMakers' ARM VN, the frontend ARM VN, or, in VPN terms, the local...