Managing VNF Lifecycle Using ETSI API
The NFVO communicates with ESC using the ETSI MANO API for lifecycle management of a VNF. A configuration template, the Virtual Network Function Descriptor (VNFD) file describes the deployment parameters and operational behaviors of a VNF type. The VNFD is used in the process of deploying a VNF and managing the lifecycle of a VNF instance.
The lifecycle operations of a VNF instance is as follows:
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Create a VNF Identifier—ESC generates a new VNF Instance Id (a universally unique identifier) that is subsequently used as a handle to reference the instance upon which to execute further operations.
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Instantiate / Deploy VNF—As part of VNF instantiation, ESC instantiates a new VNF instance in the VIM. ESC receives a request to instantiate a VNF instance from NFVO. The instantiate request contains resource requirements, networking and other service operational behaviors. All these requirements along with the VNFD and the grant information provides all the necessary information to instantiate the VNF.
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Operate VNF—ESC allows you to start and stop a VNF instance. The resources are not released or changed, but the VNF instance in the VIM is toggled between these two states.
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Query VNF—To query one or more VNF instances known to ESC. To query one or more VNF instances known to ESC. This is a specific REST end point that can be filtered to find specific instances. The instances can be filtered using the VNF Instance Id.
Also, a separate REST end point allows the NFVO to query the status of one or more lifecycle operation occurrences associated with a VNF. The lifecycle operations can be filtered using a specific occurrence identifier.
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Modify VNF—ESC allows you to modify the properties of a single VNF instance. The instantiated VNF is updated, and the lifecycle management operation occurrence sends notification to the NFVO about the status of the VNF.
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Scale and Scale to Level VNF—ESC allows you to scale VNFs in two ways. You can scale a VNF incrementally, or to a specific level.
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Heal VNF—ESC heals the VNF when there is a failure.
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Terminate / Undeploy VNF—To terminate the VNF instance in the VIM. The resources themselves remain reserved for the VNF instance, however the VNF itself is undeployed.
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Delete VNF Identifier—The resources are fully released in the VIM and in ESC and the associated VNF instance identifer is also released.
For VNF lifecycle operations using REST and NETCONF APIs, see Configuring Deployment Parameters.