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Infrastructure Controllers typically execute OpenStack requests for the creation of virtual machines (VMs), and load the Virtual Function (VF) software into the new VM container. To do this, the Infrastructure Controller obtains the Virtual Function's Resource workflow from the SDC. The Resource workflow will define defines VM sizing, including compute, storage, and memory. When the Infrastructure Controller completes the request, it will pass passes the virtual resource identifier and access (IP) information back to the MSO to provide to the Network and Application controllers.
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If the Resource workflow requires multiple VMs, the MSO will repeat repeats the process, requesting each Infrastructure Controller to spin up one or more VMs and load the appropriate VFs.
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Application Controllers
The MSO requests Application Controllers will be requested by the MSO to obtain the application-specific component of the Service workflow from SDC and to execute the orchestration workflow. The The MSO continues to be responsible for ensuring that the Application Controller successfully completes its Resource configuration as defined by the workflow.
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OpenECOMP includes a generic Application Controller (APP-C) that receives commands from OpenECOMP components, such as MSO, DCAE, or the Portal, and uses these commands to manage the life cycle lifecycle of Services, Resources (virtual applications and Virtual Network Functions), and their components. See the <<DocRef: Application Controller (APP-C) API Guide>>.