From 8e0097cb7937cf9f88687403816c8a960bfc126a Mon Sep 17 00:00:00 2001 From: Toshiaki Takahashi Date: Tue, 14 Jul 2020 13:11:40 +0900 Subject: [PATCH] VNF Workflows Customization by Action Driver ETSI NFV doesn't define Lifecycle Management (LCM) workflow behaviors. Currently, Tacker has a default LCM workflow, VNF vendors can't change the default workflow. The default workflow doesn't satisfy some VNF's LCM requirements. We want to enable VNF vendor to customize their workflows by Action Driver. Change-Id: I49dce1bc2bfded9f69fdea1c1a48636af59d1f8b Blueprint: action-driver --- specs/victoria/action_driver.rst | 311 +++++++++++++++++++++++++++++++ 1 file changed, 311 insertions(+) create mode 100644 specs/victoria/action_driver.rst diff --git a/specs/victoria/action_driver.rst b/specs/victoria/action_driver.rst new file mode 100644 index 00000000..c78baa3f --- /dev/null +++ b/specs/victoria/action_driver.rst @@ -0,0 +1,311 @@ +.. + This work is licensed under a Creative Commons Attribution 3.0 Unported + License. + + http://creativecommons.org/licenses/by/3.0/legalcode + +============================================ +VNF Workflows Customization by Action Driver +============================================ + +Problem description +=================== + +ETSI NFV doesn't define Lifecycle Management (LCM) workflow behaviors. +Currently, Tacker has a default LCM workflow, VNF vendors can't change the default workflow. +The default workflow doesn't satisfy some VNF's LCM requirements. + +* For healing, evacuation is used instead of deletion and creation. + +We want to enable VNF vendor to customize their workflows by Action Driver. + +Proposed change +=============== + +This proposal suggests providing the Action Driver function to flexibly choose +customized LCM workflows. Expanding Tacker's ability is best accomplished with +a driver model similar to the existing Management and Infrastructure Drivers. + +Currently, Mgmt Driver function configures applications provided by VNF vendors. +So we should also enable VNF vendors to customize configuration methods +for applications via Mgmt Driver. + +These customizations are specified by "interface" definition in +ETSI NFV-SOL001 [#NFV-SOL001]_ "6.7 Interface Types". + +Overview of Action Driver function is as follows +(Concrete non-standard driver implementations are future works. +Only import Python implementation drivers is the first scope.): + +:: + + +------------------+ interface of Lifecycle + | | +-----------------+ +-----------------+ +----------------+ + | | | | | | | | + | VNFM API +------->+ VNF Lifecycle +-----+-->+ Action Driver +---------->+ Infra Driver | + | | | Management | | | | | | + | | | | | | +-+ | +-+ + | | +-----------------+ | +-+---------------+ | +-+--------------+ | + +------------------+ | | [standard] | | OpenStack_T | + | | Instantiate | | OpenStack_V | + | | Heal_evacuate | | Kubernetes_3 | + | | Heal_recreate | | : | + | | | +----------------+ + | | [custom] | + | | Heal_evacuate | + | | | + | | [mistral WF] | + | | (Future work) | + | | Instantiate_ | + | | VNF_A | + | | Instantiate_ | + | | VNF_B | + | | | + | +-----------------+ + | + | +----------------+ + +---->+ | + interface of | Mgmt Driver | + Lifecycle start/end | | + (xxx_start/xxx_end) | +-+ + +-+--------------+ | + | Ansible | + | cloud+init | + | Kubernetes | + | : | + +----------------+ + + +Flow of instantiation of a VNF instance with Action Driver is as follows: + +:: + + +----------+ +---------------+ +-----------+ +---------------+ +--------------+ + | | | | | | | | | | + | VNFM API | | VNF Lifecycle | | Tacker DB | | Action Driver | | Mgmt Driver | + | | | Management | | | | | | | + | | | | | | | | | | + +----+-----+ +------+--------+ +-----+-----+ +-------+-------+ +------+-------+ + | | | | | + | Instantiate VNF | | | | + +------------------> | | | + <- - - - - - - - - + Fetch action | | | + | (async) | from vnfd_dict | | | + | | | | | + | +-------------------> | | + | <-------------------+ | | + | | | | | + | | | | | + | | mgmt_call( | | | + | | method='instantiate_start') | | + | | | | | + | +----------------------------------------------------------->| + | <------------------------------------------------------------+ + | | | | | + | | | | | + | | action_call( | | | + | | method='action_instantiate_vnf') | | + | | | | | + | +---------------------------------------> +------+ | + | | | | |Infra | | + | | | | |Driver| | + | | | | +---+--+ | + | | | | | | + | | | | | | + | | | | instantiate_vnf | + | | | | | | + | | | +---------> | + | | | <---------+ | + | <---------------------------------------+ | | + | | | | + | + | | | | | + | | mgmt_call( | | | + | | method='instantiate_end') | | + | | | | | + | +----------------------------------------------------------->| + | <------------------------------------------------------------+ + | | | | | + | | | | | + + + + + + + +How to Define the Drivers +------------------------- +Action Driver and Mgmt Driver are specified by VNFD. + +How to specify Action Driver is as follows: + +:: + + node_templates: + VNF: + type: tacker.sample.VNF + properties: + flavour_description: A simple flavour + interfaces: + Vnflcm: + instantiate: + implementation: action-drivers-custom + . + . + . + artifacts: + action-drivers-custom: + description: Action driver standard + type: tosca.artifacts.Implementation.Python + file: /usr/local/lib/python3.6/site-packages/tacker/vnfm/action_drivers/custom_action_driver_1.py + +How to specify Mgmt Driver is as follows: + +:: + + node_templates: + VNF: + type: tacker.sample.VNF + properties: + flavour_description: A simple flavour + interfaces: + Vnflcm: + instantiate: [] + instantiate_start: + implementation: mgmt-drivers-noop + instantiate_end: + implementation: mgmt-drivers-custom + terminate: [] + terminate_start: [] + terminate_end: [] + + artifacts: + mgmt-drivers-custom: + description: Management driver custom + type: tosca.artifacts.Implementation.Python + file: /usr/local/lib/python3.6/site-packages/tacker/vnfm/mgmt_drivers/custom_mgmt.py + + artifacts: + mgmt-drivers-noop: + description: Management driver noop + type: tosca.artifacts.Implementation.Python + file: /usr/local/lib/python3.6/site-packages/tacker/vnfm/mgmt_drivers/noop.py + +In the case that we use artifacts in VNF package, +we write relative path as the value of 'file:' in 'artifacts:' block. + +The following is the default VNFD description +which specify all driver implementations as standard. +i.e. We can customize the following implementations. + +:: + + interfaces: + Vnflcm: + instantiate: [] + instantiate_start: [] + instantiate_end: [] + terminate: [] + terminate_start: [] + terminate_end: [] + heal: [] + heal_start: [] + heal_end: [] + scale: [] + scale_start: [] + scale_end: [] + + +Action Driver Directories Structure +----------------------------------- +This spec proposes the creation of a "action_drivers" under tacker/vnfm. + +:: + + tacker + |-- plugin.py + |-- vnfm + |-- action_drivers + |-- abstract_driver.py + |-- custom_action_driver_1.py + |-- custom_action_driver_2.py + : + +Alternatives +------------ + +None + +Data model impact +----------------- + +None + +REST API impact +--------------- + +None + +Security impact +--------------- + +None + +Notifications impact +-------------------- + +None + +Other end user impact +--------------------- + +Users can specify LCM action and pre/post setting with VNFD. + +Performance impact +------------------ + +None + +Other deployer impact +--------------------- + +None + +Developer impact +---------------- + +None + +Implementations +=============== + +Assignee(s) +----------- + +Primary assignee: + +1. Toshiaki Takahashi + +Work Items +---------- + +* Action Driver main process +* Cooperation with existing Mgmt Driver Framework +* Calling Action Driver process from LCM process +* VNFD reading and Action Driver setting +* Unit tests +* Functional tests + +Dependencies +============ + +Testing +======= + +Unit and functional tests are sufficient to test specified process +written in VNFD is called correctly. + +Documentation Impact +==================== + +* Add document about how to customize LCM with Action Driver + +References +========== + +.. [#NFV-SOL001] https://www.etsi.org/deliver/etsi_gs/NFV-SOL/001_099/001/02.06.01_60/gs_NFV-SOL001v020601p.pdf