Importing a virtual appliance from OVA
Not all virtual machines have to be built from scratch or built from a template that you've created in-house. Many virtual machines are distributed in appliance form using the OVA and OVF formats. OVA is a single file that contains all of the details and virtual disk information for a virtual machine.
OVF is a set of files that contains specifications and the data disks for a virtual machine. These two formats allow vendors to create pre-defined copies of their application and easily distribute them for use.
Importing a virtual appliance from PowerCLI is actually a pretty simple task to accomplish, but it does come with a bit of risk. Not all virtual appliances are created in a way such that importing them from PowerCLI will work. For instance, the vCenter Server Appliance (VCSA) is not a great candidate for importing in PowerCLI because it requires a lot of additional configuration questions to be answered during the import wizard. Without these settings...