SO-ETSI-VNFMAdaptor for Dublin Presentation slide deck at ONAP Paris 2019
- JIRA ONAPARC-310
(SO Adapter which uses SOL003 to connect to S/G VNFM)
SO-ETSI Alignment Use Cases for Dublin
Leverage ETSI standards for VNF LCM in SO
Build SO VNFM Adapter
Use SOL003 APIs (2.5.1) for VNF LCM
Support operations such as create, instantiate, grant, query, etc.
Enhance SO BPMN workflows & recipes
Policy based VNF scale out thru VNFM Adapter (Stretch Goal)
VNFM Adapter interfaces for VES event
Policy Framework for scaling decisions
SO workflows for VNF Scale out
VNF-Level Assignment modeling in SDNC and A&AI (open issue)
VNF Application Configuration thru VNFM Adapter and VNFM (open issue)
SO VNFM Adapter Requirements for Dublin
New SO sub-component, following ONAP Microservice Architecture
Generic VNFM Adapter, supporting SOL003-compliant SVNFMs
- Support SOL003 APIs for VNFM LCM
- VNF Package management (Download & Parse VNF Package)
- Get package files from the SDC repository thru SO
- SO Catalog DB enhancement for SOL001/SOL004 is under discussion, for future release
- Invoking SVNFM based on SOL003 VNF LCM APIs as a client
- Granting, based on ETSI VNFLifecycleOperationGranting
- Subscription to SVNFM for getting notifications
- STARTING, PROCESSING, COMPLETED
- SVNFM selection based on configuration values that are configured during VNF on-boarding and VNFM registration. Two methods are considered:
- Correlation between VNF NF Type and VNFM Type (Nokia method)
- Utilizing VNFD vnfm_info:type, VNFM registration values: VNFM type, Cloud region, vendor
SVNFM Requirements for Dublin
- Vendor SVNFM must be "SOL003-compliant"
- Providing SOL003 APIs for VNFM LCM, based on ETSI VNFLifecycleManagement
- Registration itself to ONAP (thru A&AI ESR) - Name, Type, Vendor, Version, URL, VIM, Username and Password
- Providing Subscription Services for Life-cycle Management Notifications
- Support of the "Direct Mode" of Resource Management only
- After receiving a grant permission, the VNFM sends requests for resources directly to VIM
- Invoking MultiCloud from VNFM is under discussion
- The "Indirect Mode" of Resource Management is being discussed, but not for Dublin
VNFM Adapter Component Architecture
- The following diagram depicts the component architecture.
- The VNFM Adapter will be a SO sub-component; packaged as a docker and running in a container.
- Communications between the VNFM Adapter and SVNFM will be SOL003 API-based.
- Communications between the SO BPMN Infra VNFM Adapter REST Client and the VNFM Adapter NBI will be SO-specific; i.e., it does not follow ETSI standards at this time.
- SO SDC Controller receives SOL001/SOL004-based CSAR from SDC, and stores the CSAR reference URLs to TOSCA_CSAR database table.
- It is assumed that SDC keeps the original vendor VNF packages in their repository, and VNFM Adapter retrieves the original vendor CSAR files from the repository.
- New VNF-level workflows that use VNFM Adapter will be implemented, and these new workflows will be invoked from the (Network) Service-level workflows based on VNF type and other criteria.
- Unlike the existing SO VNF/VF-Module workflows, the new VNF-level workflows will NOT interact with OpenStack directly. The workflows will delegate the VNF LCM requests to VNFM Adapter, and VNFM Adapter will delegate the requests to VNFM further. Then, VNFM will interact with VIM directly. In Dublin release, the direct mode of resource management will be supported as depicted above.
- Use Cases
- SOL001/SOL004 Support
- SOL003 API Support
- SO VNFM Adapter SOL003 API Support Design
- VNFM Adapter VNF Package Management
- SO BPMN Infra & VNFM Adapter Run-time Scenario
- SDNC Assignment Management
- VNFM Adapter Locating SVNFM
- VNF Life-cycle Granting
- VNFM Adapter Homing Decision for VNF Granting
- VNF and VF-Module Deduction
VNFM Adapter Design
- SO VNFM Adapter component (a sub component of SO; docker image and container manged)
- North Bound Interface (NBI)
- RESTful APIs that support createVnf, instantiateVnf, queryVnf, grantVnf
- Its APIs are SO specific; i.e., not SOL003-based ones
- Business Logic layer
- It is invoked by the NBI and provides business logic for createVnf, instantiateVnf, queryVnf
- SDNC and A&AI access to collect assignment and VimConnectionInfo
- Access SdcPackageProvider for getting SOL003 package(s) and parameters
- SdcPackageProvider
- Supports SOL001/SOL004 package management
- Provides getPackage, getVnfdId, getFlavorId, getVnfNodeProperty
- Provides getPackage(s), getVnfd, getArtifactFile for SVNFM
- Uses SDC Tosca Parser
- GrantManager
- Provides requestGrantForInstantiate REST API for SVNFM
- Invokes OOF for homing decision; HPA support
- SOL003Lcn APIs
- Support VnfIdentifierCreationNotification, VnfIdentifierDeletionNotification, VnfLcmOperationOccurrenceNotification
SOL001/SOL004 Support & Design
CSAR Import, Store and Retrieve Sequences
- SO SDC Controller gets a SOL004 VNF package with an SOL001 VNFD
- SO SDC Controller stores a VNF CSAR file reference to the SO Catalog DB (e.g., TOSCA_CSAR database table)
- VNFM Adapter gets a CSAR package URL from the SO TOSCA_CSAR database table
- VNFM Adapter gets an original CSAR package file from the SDC repository
- It is assumed that the Adapter retrieves the original vendor provided CSAR package from SDC repository directory before it passes the package to SVNFM, where SVNFM handles the original CSAR. For that, SDC copy the full original package.
- There would be two CSAR packages for a service: one original package, one SDC transformed package.
- VNFM Adapter passes the original CSAR package to SVNFM because the SVNFM is outside of ONAP and is designed to handle the vendor CSAR package.
Note: SO future release could consider SOL001/SOL004 internal representation in its Catalog DB, or using the Run-time Catalog DB
VNFM Adapter Run-time Scenarios
- The following diagram depicts BPMN Infra and VNFM Adapter Run-time scenarios.
- SO BPMN Service workflows dispatch new resource-level workflows based on VNF request parameters (e.g., type, others).
- SO BPMN VNF-level resource workflows handle:
- Assign VNF Network to SDNC
- Retrieve the Network Assignment from SDNC
- Invoke VNFM Adapter Client with required parameters
- VNFM Adapter Client manages:
- Populate parameter structures based on data from SO workflows
- Invoke VNFM Adapter NBI with required parameters
- VNFM Adapter gets GenericVNF from A&AI
- VNFM Adapter locates the corresponding VNF and VNFM registration info form A&AI (ESR). Two methods are suggested
- Current one: based on VNF NF Type and VNFM Type in A&AI
- Could use VNFD vnfm_info:type, VNFM registration values: VNFM type, Cloud Region, vendor - logic is being designed
- VNFM Adapter gets VimConnectionInfo from A&AI
- Queries A&AI based on the cloud region and tenant id
- Builds the VimConnectionInfo based on the type, service-url, user-name, password, cloud-domain, etc.
- VNFM Adapter uses network assignment (e.g., IP Address) from SO (thru SDNC) and builds the extVirtualLinks and other parameters.
VF-Module Deduction from SOL001
- There is an assumption that SDC transforms the vendor provided VNF package into ONAP-compliant one; i.e., deducing VF Modules based on VNFD ScalingAspects and Delta.
- If SDC supports the transformation in Dublin time-frame, the transformed CSAR will be imported to SO, and SO VNF- and VF-Module-level workflows will manage VNF and VF Module topology towards SDNC with the following changes - Input from Gil Bullard (AT&T)
- Today the VNF-level workflow has an embedded per-VF Module loop that a) retrieves the SDNC assignments for that VF Module, and then b) sends those VF Module-level assignments down to the VIM (e.g., OpenStack); the loop then moves to repeat "a" with the next VF Module.
- The new VNF-level flow will have the following sequences:
- an embedded per-VF Module loop that only retrieves the SDNC assignments for each VF Module; because the VIM is hidden from SO's sight, beneath the VNFM Adapter/VNFM.
- After finishing the loop, the SO workflows will send a structure to the VNFM Adapter that includes the aggregate assignments at the VNF level.
- The VNFM Adapter aggregates all the VF-Module level assignments and transforms the assignment data into SOL003 API parameters before sending them to SVFNM
- The VNFM Adapter would need to be able to parse the VNF-level assignments structure received from SO to obtain the per-VDU connection point assignments information and any per-VDU parameter information (e.g., hostnames)
- In doing so, the VNFM Adapter would need to know to ignore the VF Module groupings of these assignments
- Further know how to map the ONAP data structure and parameter names into the ETSI (e.g., VM=VDU, VNFC=VNFC, vNIC=vNIC, etc.). Note that the above assumes that in ONAP, as in ETSI, there will be a one-to-one correspondence between VM/VDU and VNFC.
Assumptions for deducing VF-Module from SOL001 (Gil Bullard's input)
- SOL001 concept of Aspect+ScalingDelta combination is one to one with the ONAP concept of VF Module.
- SOL001 concept of VDU is one to one with the ONAP concept of A&AI vServer
- SOL001 concept of a connection point associated with a VDU corresponds to the ONAP concept of the same name, as does the understanding of the meaning of “internal” versus “external” connection point.
- ONAP-compliant SOL001 VNF Vendors will be obliged to name their HEAT files using a naming convention that encodes the SOL001 Aspect+ScalingDelta names
- ONAP-compliant SOL001 VNF Vendors will be obliged to name their SOL001 Aspect+ScalingDelta parameters using a naming convention that readily maps to the corresponding HEAT properties.
- In addition, if AT&T has already deployed such a vendor’s VNF into its network, the HEAT naming will remain invariant, and (at least) the (AT&T version of that) SOL001 be written to match it.
- What to do
- ONAP will be extended to incorporate the constructs of Aspect and Scaling Level. This includes SDC’s, SOs, and A&AI’s modeling of these constructs and A&AI's ability to capture and SO’s ability to set/update the "current scaling level" of a VNF for a given Aspect.
- If ETSI in their SOL001 VNFD had defined a "ScalingDelta" in a straightforward manner, i.e., in terms of the VNFCs that comprise it, then it would be very easy to extract VF Module information from the VNFD. (I would like to see ETSI define "ScalingDelta" in this manner, as opposed to the current way they do so. ) However, given that they did not, ONAP SDC would need to be extended to derive the VF Module “structure” from the SOL001 document through the algorithm below. “Structure” in this case includes the VDU topology, connection points and associated parameters. This algorithm will:
- Determine the set of Aspects and corresponding VDUs and associated ScalingDeltas (step_deltas) from the SOL001.
- Determine the set of ScalingLevels associated with each Aspect and the ScalingDeltas associated with each.
- Translate the VDU-centric representation of ScalingDeltas (step_deltas) as per SOL001 to come up with a ScalingDelta-centric representation that captures the number and type of VDUs associated with that ScalingDelta across the various VDU types.
- Create a VF Module object that corresponds to each ScalingDelta-centric representation of a ScalingDelta calculated above.
- Fill in the details of the VF Module object based on the SOL001 data to represent the VDU connection points, associated Networks (internal or external), and associated Parameters.
- Determine if there is an the artifact in the SOL004 package that is a HOT YAML whose file name corresponds (through a VNF vendor obligatory naming convention) to the Aspect+ScalingDelta from which this VF Module object was derived. If so, associate that HOT file with the VF Module.
- Name the VF Module based on a naming convention to capture the Aspect+ScalingDelta names
- Determine and capture the mapping from each Aspect + ScalingLevel model for the VNF to the corresponding VF Module.
- Given a desired state Aspect+ScalingLevel, will be able to calculate (from the SDC distributed mapping of Aspect+ScalingLevel to VF Module along with the current Scaling Level for this Aspect as per A&AI) the (ordered set of) VF Module(s) needed to take that VNF from the “current scaling level” to the desired level for that Aspect.
- Note: As an aside, SDC enhancements are being discussed. It is not clear if the SDC changes will be available in the Dublin time frame. some “stubbing off” SDC with a simulator could be suggested to at least prove in the run-time aspects of the solution.
VNFM Adapter VNF Package Management
VNF Package Management Interface
- VNFM Adapter supports VNF Package Management Interface
- Accepts the "Get VNF packages" request and returns VnfPkgInfo[]
- Accepts the "Get VNFD" request and returns Vnfd
- Accepts the "Get VNF artifact" request and return Artifact file
VNFM Adapter Locating SVNFM
- VNFM Adapter locates a proper SVNFM based on VNF NF Type/VNFD and VNFM registration
- Two methods are suggested as follows, and one of them will be chosen.
- Current method
- VnfLCM::locateVnfm(GenericVnf vnf)
- Get a vnfm list from AAI ESR
- Find a matched Vnfm, where vnfmInfo.getType() == vnf.getNfType
- New method
SOL003 Support and Design
SOL003 Interfaces between VNFM Adapter (Client) and SVNFM (Provider)
Create VNF
HTTP Method Type: POST
VNFM Endpoint: /vnf_instances/
Request Payload: CreateVnfRequest
Response Header: 201 success
Response Body: VnfInstance
Instantiate VNF
HTTP Method Type: POST
VNFM Endpoint: /vnf_instances/{vnfInstanceId}/instantiate
Request Payload: InstantiateVNFRequest
Response Header: 202 success
Response Body: not applicable
Query VNF Instances
HTTP Method Type: GET
VNFM Endpoint: /vnf_instances (for multiple VNFs), /vnf_instances/{vnfInstanceId} (for single VNF)
Request Payload: not applicable
Response Header: 200 success
Response Body: VnfInstance[] (for multiple VNFs), VnfInstance (for single VNF)
SOL003 Interfaces between SVNFM (Client) and VNFM Adapter (Provider)
- HTTP Method Type: POST
VNFM Endpoint: /grants
Request Payload: GrantRequest
Response Header: 201 success
Response Body: not applicable
The purpose of the grant request is to have the VNFM’s resource request authorized by VNFM Adapter/SO and to get advice on where to allocate resources such as virtual machines based upon capacity.
Grant requests are also useful to ensure that all resources (capacity, quota, flavors, SRTs, etc.) required for successful VNF deployment are available.
There are two Grant Response modes, synchronous and asynchronous. Synchronous response mode will be supported for Dublin.
Synchronous Mode
VNFM sends a POST request to the Grant resource with a “GrantRequest” in the body
VNFM Adapter with SO makes the granting decision
VNFM Adapter with SO returns to VNFM a “201 Created” response with a “Grant” data structure in the body
- VNFM sends a POST request to the Grant resource with a “GrantRequest” in the body
- VNFM Adapter with SO returns to VNFM a “202 Accepted” response with an empty body, and a “Location” header indicates a callback URL
- VNFM Adapter with SO makes the granting decision
- VNFM keeps trying to obtain the grant by sending a GET request to VNFM Adapter until a “200 OK” response with a “grant” data in the body
- VNFM Adapter finishes the granting process and returns a “200 OK” response with a “Grant” data in the body
VNFM Adapter Homing Decision for VNF Granting
- Note: the following logic concept is inspired by the VFC Homing decision mechanism.
- Use of OOF is optional. For those models without using HPA, VNFM Adapter will make a grant decision based on VIM registration information.
- VNFM Adapter sends out homing requests to OOF (OSDF) containing resource info
- OOF (OSDF) pulls all the related homing constraints from Policy
- OOF (HAS) checks AAI database to pull region (flavor) information
- OOF (HAS) communicates with Multi-Cloud to check cloud capacity (vims which fulfill the requirements)
- OOF (OSDF) returns homing allocation solution to VNFM Adapter
- OOF collects information as following:
- Service and Resource Info, from: AAI
- HPA Flavors/Capabilities/Capacity Info, from: AAI
- Policy Models (Homing, PCI) from: Policy
- Infrastructure Metrics Info (capacity), from: MultiCloud
- Cloud Agnostic Intent Info, from: MultiCloud
- PCI configuration data (not yet a part of SDC model)
More SVFM SOL003 Interfaces for Future Release
Scale VNF
HTTP Method Type: POST
- VNFM Endpoint: /vnf_instances/{vnfInstanceId}/scale
- Request Payload: ScaleVnfRequest
- Response Header: 202 accepted
- Response Body: not applicable
- Scale to Level Vnf
- HTTP Method Type: POST
- VNFM Endpoint: /vnf_instances/{vnfInstanceId}/scale_to_level
- Request Payload: ScaleVnfToLevelRequest
- Response Header: 202 accepted
- Response Body: not applicable
Terminate VNF
HTTP Method Type: POST
VNFM Endpoint: /vnf_instances/{vnfInstanceId}/terminate
Request Payload: TerminateVnfRequest
Response Header: 202 success
Response Body: not applicable
- Delete VNF
HTTP Method Type: DELETE
VNFM Endpoint: /vnf_instances/{vnfInstanceId}
Request Payload: not applicable
Response Header: 204 success
Response Body: not applicable
- Operate VNF
HTTP Method Type: POST
VNFM Endpoint: /vnf_instances/{vnfInstanceId}/operate
Request Payload: OperateVnfRequest
Response Header: 202 success
Response Body: not applicable
- SO
- SO Catalog DB for SOL001/SOL004 support
- BPMN Workflows and Recipes
- VNFM Adapter
- SDC
- Support SOL001/SOL004
- VF Module deduction based on SOL001
- SDNC
- VNF-level Network Assignment, instead of VF-Module
- A&AI
- VNF-level Inventory Update
- VNFM location
- Policy (Stretch goal) - not for Dublin
- Scale-Out support for ETSI-based scaling
- Modeling
- Support SOL001/SOL004
- ETSI vs. ONAP-compliant VNFD
VNF Application Configuration thru VNFM Adapter and VNFM is under discussion
Better mechanism for VNFM Adaptor to locate VNFMs (two methods are suggested)
Modelling for VNF and VF Modules; mapping between VF Modules and VNF
Continue to support existing non-ETSI SO workflows along with ETSI-based workflows
VNFM Adaptor architectural direction; should it work as a thin layer or should it be evolved as a full-fledge NFVO in the future, e.g., handling grant by itself, updating resources in A&AI and SDNC?
SOL001/SOL004 SO Representation
SOL001 Package management
SDNC Preload VNF Topology
MultiCloud use