When you test a recovery plan, Site Recovery Manager can create a test network that it uses to connect recovered virtual machines. Creating a test network allows the test to run without potentially disrupting virtual machines in the production environment.
The isolated test network is managed by its own virtual switch, and in most cases recovered virtual machines can use the network without having to change network properties such as IP address, gateway, and so on. You use the isolated test network by selecting Isolated network (auto created) when you configure the test network settings while creating a recovery plan and there are no site-level mappings. An isolated test network does not span hosts. You must configure a test network for every network that a recovery plan uses during recovery.
You must recover any virtual machines that must interact with each other to the same test network. For example, if a Web server accesses information on a database, those Web server and database virtual machines should recover together to the same network.
A datacenter network is an existing network at the recovery site. You can select a datacenter network for use as a test network. To use it, recovered virtual machines must conform to its network address availability rules. These virtual machines must use a network address that the network's switch can serve and route, must use the correct gateway and DNS host, and so on. Recovered virtual machines that use DHCP can connect to this network without additional customization if the DHCP is properly configured. Other virtual machines might require IP customization and additional recovery plan steps to apply the customization.