In a typical vSphere Replication installation, the primary site provides business-critical datacenter services. The secondary site is an alternative facility to which you can migrate these services.

The primary site can be any site where vCenter Server supports a critical business need. The secondary site can be in another location, or in the same room to establish redundancy. The secondary site is usually located in a facility that is unlikely to be affected by environmental, infrastructure, or other disturbances that might affect the primary site.

vSphere Replication has the following requirements for the vSphere® configurations at each site:

Each site must have at least one datacenter.

The secondary site must have hardware, network, and storage resources that can support the same virtual machines and workloads as the primary site.

The sites must be connected by a reliable IP network.

The secondary site must have access to networks (public and private) comparable to those on the primary site, although not necessarily the same range of network addresses.

When you replicate a virtual machine using vSphere Replication, a wizard guides you through the replication process, which includes establishing a connection between the primary and secondary sites. When you replicate a virtual machine, you must pair the sites and provide authentication information for the two sites so they can exchange information. Connecting sites requires vSphere administrative privileges at both sites. You must know the user name and password of a vSphere administrator at each site.