At the time of writing this book, not all virtual network features have been migrated to ARM virtual networks. VPN is one of these features. Therefore, it is necessary to create a VN in the Service Manager mode to configure a VPN to have safe access from the CloudMakers office. As we have two VNs, it is also necessary to have a safe and privileged access from the frontline ARM VN to this backend VN.
Configuring VN in the classic mode is quite different from ARM. The configuration in the service is XML-based (not JSON-based, like ARM), and it has no specific API. You need to write some XML to configure your VN. One issue is that you can change or create your VN only at the account level. There is only one network configuration XML that contains the network configuration of the entire account. Making changes to this configuration for a project can affect your other deployments.