vCenter Server provides a licensing infrastructure that you can use for management and reporting of licenses that apply to ESXi hosts, vCenter Server, and certain solutions such as vCenter Site Recovery Manager, vCenter CapacityIQ, vCenter Chargeback, and so on.
Licensing in vCenter Server is implemented using license keys. You can assign one license key to multiple licensable objects of the same type if the key has enough capacity. However, you cannot assign multiple license keys to a single licensable object.
For example, you can assign one license key to multiple vCenter Server systems in a Linked Mode group, but you cannot assign multiple license keys to a single vCenter Server system.
ESXi 5.0 hosts, vCenter Server 5.0, and solutions have different licensing models.
§ ESXi 5.0 hosts are licensed with vSphere 5.0 license keys that have per-processor capacity with pooled
§ vRAM entitlements. When you assign a vSphere 5.0 license key to an ESXi 5.0 host, the amount of license capacity that is consumed is equal to the number of processors in the host.
§ vRAM is a licensing-specific measure for the memory that is configured for powered-on virtual machines that run on ESXi 5.0 hosts. The memory that is configured for powered-on virtual machines on ESXi 5.0 hosts counts against the pooled vRAM entitlements of vSphere 5.0 license keys.
§ vRAM entitlements are pooled across all assigned vSphere 5.0 license keys of the same edition for a single vCenter Server system or a Linked Mode group.
vCenter Server 5.
§ vCenter Server 5.0 systems are licensed with vCenter Server 5.0 license keys that have per-instance capacity type.
§ A license key for vCenter Server determines the number of vCenter Server instances that you can license with the key.
Solutions are licensed depending on their specifics.
For example, vCenter Site Recovery Manager, vCenter Capacity IQ, and vCenter Chargeback are licensed on a per-virtual-machine basis.
The licensing infrastructure in vCenter Server provides functions that you can use to implement and monitor the licensing models of ESXi hosts, vCenter Server, and solutions.