From bf04bd9a76a61718e1f33497fd7eada0d990b412 Mon Sep 17 00:00:00 2001 From: Hirofumi Noguchi Date: Fri, 15 Jul 2022 10:51:28 +0900 Subject: [PATCH] Support CNF Rollback in v2 LCM API This specification enhances version 2 (v2) of Rollback API for supporting CNF. Previous release supported VNF Lifecycle Management (LCM) operations defined in ETSI NFV SOL002 v3.3.1 and SOL003 v3.3.1. However, v2 Rollback API for CNF LCM was limited. This specification enables v2 Rollback API to handle Instantiation and Scale-out of CNF. Change-Id: I136a996cae49e8d13e1bfc7703c80137afebf320 Implements: blueprint support-nfv-solv3-error-handling --- specs/zed/support-v2-cnf-rollback.rst | 380 ++++++++++++++++++++++++++ 1 file changed, 380 insertions(+) create mode 100644 specs/zed/support-v2-cnf-rollback.rst diff --git a/specs/zed/support-v2-cnf-rollback.rst b/specs/zed/support-v2-cnf-rollback.rst new file mode 100644 index 00000000..afcd5113 --- /dev/null +++ b/specs/zed/support-v2-cnf-rollback.rst @@ -0,0 +1,380 @@ +.. + This work is licensed under a Creative Commons Attribution 3.0 Unported + License. + http://creativecommons.org/licenses/by/3.0/legalcode + + +================================== +Support CNF Rollback in v2 LCM API +================================== + +.. Blueprints: + +https://blueprints.launchpad.net/tacker/+spec/support-nfv-solv3-error-handling + +This specification enhances +version 2 (v2) of Rollback API for supporting CNF. + +Problem description +=================== + +Yoga release supported VNF Lifecycle Management (LCM) operations +defined in ETSI NFV SOL002 v3.3.1 [#NFV-SOL002_331]_ +and SOL003 v3.3.1 [#NFV-SOL003_331]_. +It also supported CNF Lifecycle Management with v2 APIs +such as Instantiate API, Terminate API, and ChangeCurrentVnfPackage API. + +However, v2 Rollback API has not completely supported CNF LCM yet. +Supporting CNF in v2 LCM API makes Tacker more powerful generic VNFM. + + +Proposed change +=============== + +This specification enhances the following API to support CNF. + +* Rollback VNF Task (POST /vnf_lcm_op_occs/{vnfLcmOpOccId}/rollback) + +v2 Rollback for Change Current VNF Package +has already been supported in Yoga release. +Also, Modify VNF Information for CNF +has already supported in v2 LCM API +because there is only common processing with VNF. +Therefore, this specification proposes +supporting v2 CNF Rollback for following APIs. + +* Instantiate VNF +* Scale-out VNF + +.. note:: Change external VNF connectivity for CNF and its rollback + are not supported because the related + standard specification has not been defined by ETSI NFV yet. + +Rollback for Instantiation +-------------------------- + +There is no change from the current implementation except for +InfraDriver (KubernetesDriver) processing. + +.. seqdiag:: + + seqdiag { + node_width = 100; + edge_length = 120; + + Client -> "tacker-server" + [label = "POST /vnf_lcm_op_occs/{vnfLcmOpOccId}/rollback"]; + Client <-- "tacker-server" [label = "Response 202 Accepted"]; + "tacker-server" ->> "tacker-conductor" + [label = "trigger asynchronous task"]; + "tacker-conductor" -> "tacker-database" + [label = "mark operation as ROLLING_BACK"]; + "tacker-conductor" <-- "tacker-database" + "tacker-conductor" ->> "tacker-conductor" + [label = "execute notification process"]; + Client <- "tacker-conductor" + [label = "POST {callback URI} (ROLLING_BACK)"]; + Client --> "tacker-conductor" [label = "Response: 204 No Content"]; + "tacker-conductor" -> "VnfLcmDriver" [label = "execute VnfLcmDriver"]; + "VnfLcmDriver" -> "KubernetesDriver" [label = "execute KubernetesDriver"]; + "KubernetesDriver" -> "Kubernetes" + [label = "call Read API to check the existence of resources"]; + "KubernetesDriver" <-- "Kubernetes" [label = "resource information if it exists"]; + "KubernetesDriver" -> "Kubernetes" + [label = "call Delete API if resources exist"]; + "KubernetesDriver" <-- "Kubernetes" [label = ""]; + "KubernetesDriver" -> "Kubernetes" + [label = "call Read API to check the status of resources"]; + "KubernetesDriver" <-- "Kubernetes" [label = "resource information"]; + "VnfLcmDriver" <-- "KubernetesDriver" [label = ""]; + "tacker-conductor" <-- "VnfLcmDriver" [label = ""]; + "tacker-conductor" -> "tacker-database" + [label = "mark operation as ROLLED_BACK"]; + "tacker-conductor" <-- "tacker-database" + "tacker-conductor" ->> "tacker-conductor" + [label = "execute notification process"]; + Client <- "tacker-conductor" + [label = "POST {callback URI} (ROLLED_BACK or FAILED_TEMP)"]; + Client --> "tacker-conductor" [label = "Response: 204 No Content"]; + } + + +The procedure consists of the following steps as illustrated in above sequence: + +Precondition: VNF lifecycle management operation occurrence is +in "FAILED_TEMP" state. + +#. The Client sends a POST request with an empty body to the "Rollback operation" + resource. +#. VNFM sends endpoints such as Client a VNF lifecycle management operation occurrence + notification with the "ROLLING_BACK" state to indicate the processing occurrence + of the lifecycle management operation. +#. VNFM sends Kubernetes a Read request to check the existence of resources. +#. If resources has been created by failed instantiate operation, + VNFM sends Kubernetes a Delete request to delete the resources. +#. VNFM sends Kubernetes a Read request + to check whether resources were deleted. +#. On successful rollback, VNFM sends endpoints such as Client + a VNF lifecycle management operation occurrence notification + with the "ROLLED_BACK" state to indicate successful completion of the operation. +#. On unsuccessful rollback, VNFM sends endpoints + such as Client a VNF lifecycle management operation occurrence notification + with the "FAILED_TEMP" state to indicate + an intermediate error (rollback failed) of the operation. + +Postcondition: The VNF lifecycle management operation occurrence +is in one of the following states: "FAILED_TEMP", "ROLLED_BACK". + + +KubernetesDriver calls following API to delete resources and check status of them. + ++------------------------+----------+-------------------------------------+ +| API Group | Type | API method | ++========================+==========+=====================================+ +| ApiregistrationV1Api | Read | read_ | +| +----------+-------------------------------------+ +| | Delete | delete_ | ++------------------------+----------+-------------------------------------+ +| AppsV1Api | Read | read_namespaced_ | +| +----------+-------------------------------------+ +| | Delete | delete_namespaced_ | ++------------------------+----------+-------------------------------------+ +| AutoscalingV1Api | Read | read_namespaced_ | +| +----------+-------------------------------------+ +| | Delete | delete_namespaced_ | ++------------------------+----------+-------------------------------------+ +| BatchV1Api | Read | read_namespaced_ | +| +----------+-------------------------------------+ +| | Delete | delete_namespaced_ | ++------------------------+----------+-------------------------------------+ +| CoordinationV1Api | Read | read_namespaced_ | +| +----------+-------------------------------------+ +| | Delete | delete_namespaced_ | ++------------------------+----------+-------------------------------------+ +| CoreV1Api | Read | read_namespaced_ | +| +----------+-------------------------------------+ +| | Delete | delete_namespaced_ | +| +----------+-------------------------------------+ +| | Read | read_ | +| +----------+-------------------------------------+ +| | Delete | delete_ | ++------------------------+----------+-------------------------------------+ +| NetworkingV1Api | Read | read_namespaced_ | +| +----------+-------------------------------------+ +| | Delete | delete_namespaced_ | ++------------------------+----------+-------------------------------------+ +| RbacAuthorizationV1Api | Read | read_namespaced_ | +| +----------+-------------------------------------+ +| | Delete | delete_namespaced_ | +| +----------+-------------------------------------+ +| | Read | read_ | +| +----------+-------------------------------------+ +| | Delete | delete_ | ++------------------------+----------+-------------------------------------+ +| SchedulingV1Api | Read | read_ | +| +----------+-------------------------------------+ +| | Delete | delete_ | ++------------------------+----------+-------------------------------------+ +| StorageV1Api | Read | read_ | +| +----------+-------------------------------------+ +| | Delete | delete_ | ++------------------------+----------+-------------------------------------+ + +The argument of Read API is ``name``. +Also, some APIs additionally require the ``namespace``. + +The arguments of Delete API are ``name`` and ``body``. +Also, some APIs additionally require the ``namespace``. +In the case of rollback operation, the body is not set. + +Rollback for Scale-out +---------------------- + +There is no change from the current implementation except for +InfraDriver processing. + +.. seqdiag:: + + seqdiag { + node_width = 100; + edge_length = 120; + + Client -> "tacker-server" + [label = "POST /vnf_lcm_op_occs/{vnfLcmOpOccId}/rollback"]; + Client <-- "tacker-server" [label = "Response 202 Accepted"]; + "tacker-server" ->> "tacker-conductor" + [label = "trigger asynchronous task"]; + "tacker-conductor" -> "tacker-database" + [label = "mark operation as ROLLING_BACK"]; + "tacker-conductor" <-- "tacker-database" + "tacker-conductor" ->> "tacker-conductor" + [label = "execute notification process"]; + Client <- "tacker-conductor" + [label = "POST {callback URI} (ROLLING_BACK)"]; + Client --> "tacker-conductor" [label = "Response: 204 No Content"]; + "tacker-conductor" -> "VnfLcmDriver" [label = "execute LCM operation"]; + "VnfLcmDriver" -> "KubernetesDriver" [label = "execute KubernetesDriver"]; + "KubernetesDriver" -> "Kubernetes" + [label = "call Read API to check the replicas of the resources"]; + "KubernetesDriver" <-- "Kubernetes" [label = "the value of replicas"]; + "KubernetesDriver" -> "Kubernetes" + [label = "call Update API to update the replicas + to the one before scaling-out + if replicas has been updated by failed scale-out operation"]; + "KubernetesDriver" <-- "Kubernetes" [label = ""]; + "KubernetesDriver" -> "Kubernetes" + [label = "call Read API to check the status of resources"]; + "KubernetesDriver" <-- "Kubernetes" [label = ""]; + "VnfLcmDriver" <-- "KubernetesDriver" [label = ""]; + "tacker-conductor" <-- "VnfLcmDriver" [label = ""]; + "tacker-conductor" -> "tacker-database" + [label = "mark operation as ROLLED_BACK"]; + "tacker-conductor" <-- "tacker-database" + "tacker-conductor" ->> "tacker-conductor" + [label = "execute notification process"]; + Client <- "tacker-conductor" + [label = "POST {callback URI} (ROLLED_BACK or FAILED_TEMP)"]; + Client --> "tacker-conductor" [label = "Response: 204 No Content"]; + } + +The procedure consists of the following steps as illustrated in above sequence: + +Precondition: VNF lifecycle management operation occurrence is +in "FAILED_TEMP" state. + +#. The Client sends a POST request with an empty body + to the "Rollback operation" resource. +#. VNFM sends endpoints such as Client + a VNF lifecycle management operation occurrence notification + with the "ROLLING_BACK" state to indicate + the processing occurrence of the lifecycle management operation. +#. VNFM sends Kubernetes a Read request to check the replicas of the resources. +#. If replicas has been updated by failed scale-out operation, + VNFM sends Kubernetes a Update request to update the replicas + to the one before scaling-out. +#. VNFM sends Kubernetes a Read request + to check whether resources were deleted. +#. On successful rollback, VNFM sends endpoints + such as Client a VNF lifecycle management + operation occurrence notification with the "ROLLED_BACK" state + to indicate successful completion of the operation. +#. On unsuccessful rollback, VNFM sends endpoints + such as Client a VNF lifecycle management + operation occurrence notification with the "FAILED_TEMP" state + to indicate an intermediate error (rollback failed) of the operation. + +Postcondition: The VNF lifecycle management operation occurrence +is in one of the following states: "FAILED_TEMP", "ROLLED_BACK". + + +.. note:: v2 VNF Rollback for Scale-out using OpenStack VIM deletes + added resources by scale-out operation. + However, v2 CNF Rollback for Scale-out using Kubernetes VIM + cannot specify deleted VNFC because the order of deletion + cannot be controlled due to Kubernetes's functionality. + This is also a constraint for v2 CNF scale-in. + +KubernetesDriver calls following API +to get current number of replicas of target resources, +updates the number of replicas, and check status of the resources. + ++------------------------+----------+-------------------------------------+ +| API Group | Type | API method | ++========================+==========+=====================================+ +| AppsV1Api | Read | read_namespaced_ 　　 | +| +----------+-------------------------------------+ +| | Update | patch_namespaced__scale | ++------------------------+----------+-------------------------------------+ + +The arguments of Read API are ``name`` and ``namespace``. + +The arguments of Update API are ``name``, ``namespace``, and ``body``. +The body is set to be the updated value of "spec.replicas" with the returned +value in Read API. + + +Data model impact +----------------- + +None + +REST API impact +--------------- + +None + +Security impact +--------------- + +None + +Notifications impact +-------------------- + +None + +Other end user impact +--------------------- + +None + +Performance Impact +------------------ + +None + +Other deployer impact +--------------------- + +None + +Developer impact +---------------- + +None + +Implementation +============== + +Assignee(s) +----------- + +Hirofumi Noguchi + + +Work Items +---------- + +* Implement KubernetesDriver processes running on Tacker-conductor. +* Add new unit and functional tests. +* Update the Tacker user guide. + +Dependencies +============ + +Tacker SPEC: Support ETSI NFV-SOL_v3 error-handling operation +[#SPEC-NFV-SOL_v3-LCM]_ + +Testing +======== + +Unit and functional test cases will be added +for v2 CNF rollback operations using Kubernetes VIM. + +Documentation Impact +==================== + +Description about v2 CNF rollback operations +will be added to the Tacker user guide. + +References +========== + +.. [#NFV-SOL002_331] + https://www.etsi.org/deliver/etsi_gs/NFV-SOL/001_099/002/03.03.01_60/gs_nfv-sol002v030301p.pdf + (Chapter 5: VNF Lifecycle Management interface) +.. [#NFV-SOL003_331] + https://www.etsi.org/deliver/etsi_gs/NFV-SOL/001_099/003/03.03.01_60/gs_nfv-sol003v030301p.pdf + (Chapter 5: VNF Lifecycle Management interface) +.. [#SPEC-NFV-SOL_v3-LCM] + https://specs.openstack.org/openstack/tacker-specs/specs/yoga/support-nfv-solv3-error-handling.html