A VDC template specifies a configuration for an organization VDC and, optionally, an Edge Gateway and organization VDC network. System administrators who want to enable organization administrators to create these resources in their organization can create VDC templates and share them with those organizations.
By creating and sharing VDC templates, system administrator can enable self-service provisioning of organization VDCs while retaining administrative control over allocation of system resources such as Provider VDCs and external networks. Organization administrators, or any role that has rights to view and instantiate VDC templates, use an instantiation operation to create organization VDCs from templates. See Create a VDC from a Template.
Provider VDC Specification
Although you can create a VDC template that specifies a single Provider VDC to support all organization VDCs instantiated from that template, you can also let the system spread organization VDC load across multiple Provider VDCs if they are present in the system. A VDC template can include multiple ProviderVdcReference elements, each of which must be paired with an external network backed by the same vCenter server that backs the Provider VDC. Each time this sort of template is instantiated, the system selects a Provider VDC and its paired network to back the organization VDC that the instantiation creates. Selection criteria are intended to choose a Provider VDC that has the necessary CPU, memory, and storage resources to support a new organization VDC.
You cannot delete a Provider VDC, external network, storage profile, or network pool referenced in a VDC template until the VDC template and all organization VDCs created from it are removed from the system.
Edge Gateway and Routed Network Specification
A VMWVdcTemplate element can specify the configuration of an Edge Gateway and an organization VDC network. These objects are created in the VDC when the template is instantiated, and an organization administrator can update them by using the workflows described in Network Administration. An organization VDC created from a template that does not include an Edge Gateway can contain only isolated networks.
Allocation Models
Every VDC template includes a VdcTemplateSpecification element that specifies a set of properties similar to those specified in the CreateVdcParams element that is used to create an organization VDC. See Create an Organization VDC with Pay As You Go Reservation Allocation Model. The subtypes of VdcTemplateSpecificationType specify one of the allocation models supported for organization VDCs. See Create a VDC Template.
