The environment in which you run the vSphere Replication virtual appliance must meet certain hardware requirements.
vSphere Replication is distributed as a 64-bit virtual appliance packaged in the .ovf format. It has a dual core CPU, a 10GB and a 2GB hard disk, and 4GB of RAM. Additional vSphere Replication Servers require 512MB of RAM.
You must deploy the virtual appliance in a vCenter Server environment by using the OVF deployment wizard on an ESXi host.
vSphere Replication consumes negligible CPU and memory on the source host ESXi and on the guest OS of the replicated virtual machine.