For a enterprise network, can we make McAfee software appliance gateway redundant with McAfee virtual appliance, or they are stand alone? And What makes the complete Solution with redundancy for Email gateway appliance with ELP? And ELP can be stand alone or simple Hardware can be standalone?
Yes you can have two of them. Sales wants to sell you this so you can buy two. At that pricing you may look at some other producers. To be straight you want get anything cheaper the prices for these SPAM Filters are almost the same. With Mcafee you pay per USER thats the only thing which is not so good. And even the leading producer just adapted their pricing this year.
Yes, you can make a physical appliance part of a cluster with a virtual appliance. You can also do a config push from one to the other and have them in a DNS round robin or the like depending on what you need.