There are four methods of adding a vCenter or a stand-alone ESXi host to the management server:
This method is recommended in most cases. The virtual appliance will be automatically deployed to every host managed by the vCenter you specify. You can select the hosts and customize the virtual appliance settings.
You may want to install Agent for VMware on a physical machine running Windows for the purpose of an offloaded or LAN-free backup.
Use if your production ESXi hosts are so heavily loaded that running the virtual appliances is not desirable.
If your ESXi uses a SAN attached storage, install the agent on a machine connected to the same SAN. The agent will back up the virtual machines directly from the storage rather than via the ESXi host and LAN. For detailed instructions, refer to "LAN-free backup".
If the management server is running in Windows, the agent will be automatically deployed to the machine you specify. Otherwise, you need to install the agent manually.
This is a necessary step after you have re-installed the management server. Also, you can register and configure Agent for VMware (Virtual Appliance) that is deployed from an OVF template.
This is a necessary step after you have installed Agent for VMware (Windows) manually or deployed Acronis Backup appliance. Also, you can associate an already configured Agent for VMware with another vCenter Server or stand-alone ESXi host.