These look like the URLs for the load balancer interfaces.
vcac.dnsdomain.com is the lif for the vCAC appliances. These render the portal and are the entry point to vCAC.
vcacweb.dnsdomain.com is the lif for the vCAC IAAS web servers. To my knowledge, these load frames into the portal for IaaS components.
vcacmgr.dnsdomain.com is the lif for the vCAC Manager service. Remember that these are active passive. It looks like in his design, this also serves as the address for load balanced DEM Orchestrators.
vcacvco.dnsdomain.com is the lif for clustered orchestrator appliances.
vcac.dnsdomain.com and vcacweb.dnsdomain.com host the web components although you only need to point your browser to vcac.dnsdomain.com.
Hope that helps.
