Support LCM notifications for VNF based on ETSI NFV-SOL specification

https://blueprints.launchpad.net/tacker/+spec/support-etsi-nfv-specs

ETSI specifications within the NFV Architecture Framework [1] describe the main aspects of NFV development and usage based on of the industry needs, feedback from SDN/NFV vendors and telecom operators. These specifications include the REST API and data model architecture which is used by NFV users and developers in related products.

Problem description

In the current Tacker implementation based on ETSI NFV-SOL, Tacker uses its own API which describes VNF lifecycle change notifications which is Ability to inform the receiver that LCM operations has been changed.

However, those operations are not aligned with the current ETSI NFV data-model. As a result, there might be lack of compatibility with 3rd party VNFs [4], as they are developed according to ETSI NFV specifications. Support of key ETSI NFV specifications will significantly reduce efforts for Tacker integration into Telecom production networks and also will simplify further development and support of future standards.

Proposed change

Introduces new interfaces to VNFM in order to notify VNF lifecycle management operations status for VNF instances. The operation provided through the interfaces are:

• Subscription (GET/POST/DELETE)

• Notification endpoint (POST)

• Individual Subscription (GET)

• individual VNF occurrence (GET)

1）Flow of managing subscriptions

• Register subscription

• Delete subscription

• Show subscription

• List subscription

• VNFM holds the Callback URL sent by consumer via “Subscription API” in advance.

• Notify the issuer of the ID associated with the received Subscription request.

• For the registered Subscription status, read by specifying ID, reading of all ID data and deletion of specified ID are allowed.

2）Flow of sending notifications

• Depending on the progress status of the sequence, VNFM send notification (Notify) to notify the status change and update the internal operation_status.

Precondition: Requesting Node has subscribed previously to notifications related to VNF lifecycle management.

• When the LCM request is accepted, the operation status is sent to the consumer which registers subscription via “Subscription API”. This will be sent for the number of registrations.

• The following operation states can be notified: STARTING/PROCESSING/COMPLETED/ROLLINGBACK/ROLLEDBACK/FAILED_TEMP

• STARTING state is sent from Tacker Server, and other Operation_state notifications are sent from Tacker-Conductor.

• Modify VNF does not send STARTING state.

• NFVO which recieved notification infomation sends 204 No Content to Tacker.

3) Flow of LCM Operation with notification

• Instantiate VNF

• Scale VNF

• Heal VNF

• Terminate VNF

• Modify VNF

• Rollback

4) Flow of VNF instance resource with notification

• CereateVNFRequest

• DeleteVNFRequest

5）Flow of Getting Operation Status

Operation status can be obtained from VNFM.

• The transmission source node specifies the vnfLcmOpOccId issued at the time of subscription and reads the information about the resource in the Subscription state.

• If the VNFM information read is successful, Response 200 OK is responded.

Alternatives

None

Data model impact

Add below new tables in ‘tacker’ database. The corresponding schemas are detailed below:-

A list of added tables:

• vnf_lcm_filters

details of added table:

vnf_lcm_filters:

id id varchar(36) Not Null
subscription_uuid subscription_uuid varchar(36) Not Null
filter filter json Not Null
notification_types notification_types MEDIUMBLOB
notification_types_len notification_types_len int
operation_types operation_types MEDIUMBLOB
operation_types_len operation_types_len int

subscription_uuid will be foreign key of vnf_lcm_subscriptions.`id`. This table has current status of LCM. Table for accumulating information for each event.

vnf_lcm_op_occs:

id id varchar(36) Not Null
operation_state operation_state varchar(16) Not Null
state_entered_time state_entered_time datetime Not Null
start_time start_time datetime Not Null
vnf_instance_id vnf_instance_id varchar(36) Not Null
operation operation varchar(16) Not Null
is_cancel_pending is_cancel_pending tinyint(1) Not Null
is_automatic_invocation is_automatic_invocation tinyint(1) Not Null
operation_params operation_params json
error error json
resource_changes resource_changes json
error_point error_point int
changed_info changed_info json
created_at created_at datetime Not Null
updated_at updated_at datetime
deleted_at deleted_at datetime
deleted deleted tinyint(1) Not Null

vnf_instance_id will be foreign key of vnf_instances.`id`. This table has current status of operation occurrence

vnf_lcm_subscriptions:

id id varchar(36) Not Null
callback_uri callback_uri varchar(255) Not Null
subscription_authentication subscription_authentication json
deleted deleted tinyint(1)

This table has registration information of Subscription

REST API impact

The following restFul API will be added. This restFul API will be based on ETSI NFV SOL002 [2] and SOL003 [3].

• Name: Subscriptions

  Description: Subscribe to notifications related to VNF lifecycle management

  Method type: POST

  URL for the resource: /vnflcm/v1/subscriptions

  Request:

  Data type	Cardinality		Description
  LccnSubscriptionRequest	1		Parameters for the Subscription.

  Attribute name	Data type	Cardinality	Supported in (V)
  filter	LifecycleChangeNotificationFilter	0..1	Yes
  callbackUri	Uri	1	Yes
  authentication	SubscriptionAuthentication	0..1	Yes

  Response:

  Data type	Cardinality	Response Codes	Description
  LccnSubscription	n/a	Success 201 Redirection 303 Error 4xx	The subscription has been created successfully.

• Name: List Subscriptions

  Description: Request to list all existing subscriptions

  Method type: GET

  URL for the resource: /vnflcm/v1/subscriptions

  Request:

  Data type	Cardinality	Description	Supported in (V)
  filter	0..1	Filter to list subscriptions	No

  Response:

  Data type	Cardinality	Response Codes	Description
  LccnSubscription	n/a	Success 200 Error 400 4xx	The list of subscriptions has been queried successfully.

• Name: Query Subscriptions

  Description: Request to show individual subscription resource by its id

  Method type: GET

  URL for the resource: /vnflcm/v1/subscriptions/{subscriptionId}

  Request:

  Name	Description
  subscriptionId	Identifier of the subscriptions.

  Response:

  Data type	Cardinality	Response Codes	Description
  LccnSubscription	n/a	Success 200 Error 400 4xx	The operation has completed successfully.

• Name: Delete Subscriptions

  Description: Request to delete individual subscription resource by its id

  Method type: DELETE

  URL for the resource: /vnflcm/v1/subscriptions/{subscriptionId}

  Request:

  Name	Description
  subscriptionId	Identifier of the subscriptions.

  Response:

  Data type	Cardinality	Response Codes	Description
  n/a	n/a	Success 204 Error 400 4xx	The individual subscription resource has been deleted successfully.

• Name: Notification endpoint

  Description: Send notifications related to VNF lifecycle changes

  Method type: POST

  URL for the resource: The resource URI is provided by the client when creating the subscription.

  Request:

  Data type	Cardinality	Description
  VnfLcmOperationOccurrenceNotification	1	A notification about lifecycle changes triggered by a VNF LCM operation occurrence.
  VnfIdentifierCreationNotification	1	A notification about lthe creation of a VNF identifier and the related individual VNF instance resource.
  VnfIdentifierDeletionNotification	1	A notification about the deletion of a VNF identifier and the related individual VNF instance resource.

  Attribute name	Data type	Cardinality	Supported in (V)
  id	Identifier	1	Yes
  notificationType	String	1	Yes
  subscriptionId	Identifier	1	Yes
  timeStamp	DateTime	1	Yes
  notificationStatus	Enum (inlined)	1	Yes
  operationState	LcmOperationStateType	1	Yes
  vnfInstanceId	Identifier	1	Yes
  operation	LcmOperationType	1	Yes
  isAutomaticInvocation	Boolean	1	Yes
  vnfLcmOpOccId	Identifier	1	Yes
  affectedVnfcs	AffectedVnfc	0..N	Yes
  affectedVirtualLinks	AffectedVirtualLink	0..N	Yes
  affectedVirtualStorages	AffectedVirtualStorage	0..N	Yes
  changedInfo	VnfInfoModifications	0..1	Yes
  changedExtConnectivity	ExtVirtualLinkInfo	0..N	No
  error	ProblemDetails	0..1	Yes
  _links	LccnLinks	1	Yes

  Response:

  Data type	Cardinality	Response Codes	Description
  n/a	n/a	Success 204 Error 4xx	The notification has been delivered successfully.

Note

virtualLinkDescId, one of the attribute contained in affectedVirtualLinks, is removed upon SOL003 version 2.6.1. However, in order to enable Tacker to expand a wide range of NFV compliant product, virtualLinkDescId will be supported in Victoria release.

• Name: Query VNF occurrence

  Description: Request to show individual VNF lifecycle management operation occurrence by its id

  Method type: GET

  URL for the resource: /vnflcm/v1/vnf_lcm_op_occs/{vnfLcmOpOccId}

  Response:

  Data type	Cardinality	Response Codes	Description
  VnfLcmOpOcc	1	Success 200 Error 4xx	The operation has completed successfully.

  Attribute name	Data type	Cardinality	Supported in (V)
  id	Identifier	1	Yes
  operationState	LcmOperationStateType	1	Yes
  stateEnteredTime	DateTime	1	Yes
  startTime	DateTime	1	Yes
  vnfInstanceId	Identifier	1	Yes
  grantId	Identifier	1	No
  operation	LcmOperationType	1	Yes
  isAutomaticInvocation	Boolean	1	Yes
  operationParams	Object	1	Yes
  isCancelPending	Boolean	0..N	No
  cancelMode	CancelModeType	0..N	No
  error	ProblemDetails	0..N	Yes
  resourceChanges	Structure(inlined)	0..1	Yes
  changedInfo	VnfInfoModifications	0..N	No
  changedExtConnectivity	ExtVirtualLinkInfo	0..1	No
  _links	LccnLinks	1	Yes

Security impact

None

Notifications impact

Tacker will creates a new subscription to notifications related to VNF lifecycle changes and send notification to consumer.

Other end user impact

None

Performance Impact

None

Other deployer impact

The previously created VNFs will not be allowed to be managed using the newly introduced APIs.

Developer impact

None

Implementation

Assignee(s)

Primary assignee:

Keiko Kuriu <keiko.kuriu.wa@hco.ntt.co.jp>

Work Items

• Add new REST API endpoints to Tacker-server for LCM notifications interface of VNF instances.

• Add features which Tacker consumes Rest API for Notifications

• Add new unit and functional tests.

• Change API Tacker documentation.

Dependencies

None

Testing

Unit and functional test cases will be added for VNF lifecycle management of VNF instances.

Documentation Impact

Complete user guide will be added to explain how to invoke VNF lifecycle management of VNF instances with examples.

References

[1]

https://www.etsi.org/technologies-clusters/technologies/NFV

[2]

https://www.etsi.org/deliver/etsi_gs/NFV-SOL/001_099/002/02.06.01_60/gs_nfv-sol002v020601p.pdf (Chapter 5: VNF Lifecycle Management interface)

[3]

https://www.etsi.org/deliver/etsi_gs/NFV-SOL/001_099/003/02.06.01_60/gs_nfv-sol003v020601p.pdf (Chapter 5: VNF Lifecycle Management interface)

[4]

https://portal.etsi.org/Portals/0/TBpages/CTI/Docs/2nd_ETSI_NFV_Plugtests_Report_v1.0.0.pdf