Learning vmware vsphere is not so difficult, but understanding the core concepts is not an easy task, until you find a perfect and professional vsphere person, who is already working on vmware vsphere projects, and Mr. Vikrant(from gettechpro) is such a person, who has been involved in dealing of installation and configuration of datacenter and cloud for more than 10 years, as he told me. He is also having good knowledge of core concepts and his way of teaching and explanation is very simple and easy