The installation guide has two parts. Installing a single cell, then adding additional cells.
If you run more than 1 cell, you will require an NFS mount for the cells to share as temporary storage.
In addition, you should have some front end load balancer for the web and console proxy services.
See for features: VMware KB 1026294
Installation: http://pubs.vmware.com/vcd-51/topic/com.vmware.ICbase/PDF/vcd_51_install.pdf - Page 23 "Creating a vCloud Director Server Group"