VMware vSphere PowerCLI is a set of Windows PowerShell snap-ins that provide cmdlets to automate vSphere and vCloud virtual environments.
VMware vSphere PowerCLI contains snap-ins of cmdlets based on Microsoft PowerShell for automating vSphere and vCloud administration. It provides C# and PowerShell interfaces to VMware vSphere and vCloud APIs.
(VMware vSphere PowerCLI Cmdlets Reference)
PowerCLI provides hundreds of cmdlets "for managing, monitoring, automating, and handling lifecycle operations for vSphere and vCloud Director components" (VMware vSphere PowerCLI User's Guide).
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