OpenStack Tacker介绍 - 8.tacker VNFD模板介绍

1、说明

    本文描述VNFD模板的结构以及基于"V1.0 CSD 03"要求的各个组成部分的字段。
    V1.0 CSD 03：http://docs.oasis-open.org/tosca/tosca-nfv/v1.0/tosca-nfv-v1.0.html

    每一个VNFD的yaml文件模板都有以下部分：

tosca_definitions_version:
   This defines the TOSCA definition version on which the template is based.
   The current version being tosca_simple_profile_for_nfv_1_0_0.

tosca_default_namespace:
   This is optional. It mentions default namespace which includes schema,
   types version etc.

description:
   A short description about the template.

metadata:
   template_name: A name to be given to the template.

topology_template:
   Describes the topology of the VNF under node_template field.
   node_template:
       Describes node types of a VNF.
       VDU:
           Describes properties and capabilities of Virtual Deployment
           Unit.
       CP:
           Describes properties and capabilities of Connection Point.
       VL:
           Describes properties and capabilities of Virtual Link.

2、节点类型

    一个VNF由VDU/s, connection point/s,virtual link/s这3个部分组成。
    每个组成部分包含 type,capabilities, properties, attributes and requirements。
    这3个组成部分位于node_templates内部。
    node_templates 包含于 topology_template 内部。
    

3、VDU

    Virtual Deployment Unit即一个有网络功能的云主机。
    type:      tosca.nodes.nfv.VDU.Tacker
    properties：定义一个VDU的属性，比如镜像，可用域，管理驱动，规格、监控策略、用户数据等。
                全量定义可以参考：tosca.nodes.nfv.VDU.Tacker
                https://github.com/openstack/tacker/blob/master/tacker/tosca/lib/tacker_nfv_defs.yaml

3.1 指定VDU属性

    一个10GB磁盘，2GB内存，2核CPU，使用cirros镜像，可用域为nova的VDU定义如下：

topology_template:
  node_templates:
    VDU1:
      type: tosca.nodes.nfv.VDU.Tacker
      properties:
        image: cirros-0.3.5-x86_64-disk
        availability_zone: nova
      capabilities:
        nfv_compute:
          properties:
            disk_size: 10 GB
            mem_size: 2048 MB
            num_cpus: 2

3.2 使用nova的flavor

    使用nova的flavor来指定VDU的属性的模板如下：

topology_template:
  node_templates:
    VDU1:
      type: tosca.nodes.nfv.VDU.Tacker
      properties:
        image: cirros-0.3.5-x86_64-disk
        flavor: m1.tiny
        availability_zone: nova

当nfv_compute properties 与 flavor同时存在的时候，优先使用flavor

3.3 VDU的监控策略

    对一个VDU进行监控，设置通过每隔20s，间隔2s连续3次ping 22端口来进行监控，
    并且重试6次，监控失败则respawn(具体驱动配置)。
    则监控策略如下：

..
  VDU1:
    type: tosca.nodes.nfv.VDU.Tacker
    properties:
      monitoring_policy:
        name: ping
          parameters:
            monitoring_delay: 20
            count: 3
            interval: 2
            timeout: 2
            actions:
              failure: respawn
            retry: 6
            port: 22

3.3 VDU用户启动数据设置

    格式如下：

..
  VDU1:
    type: tosca.nodes.nfv.VDU.Tacker
    properties:
      user_data_format: RAW
      user_data: |
        #!/bin/sh
        echo "Adding this line to demofile" > /tmp/demofile

3.4 配置VDU

   VDU可以通过管理驱动(mgmt_driver)对config内部的数据进行配置。
   具体例子的可以参考：
   https://docs.openstack.org/tacker/latest/install/deploy_openwrt.html

3.5 指定外部镜像

    artifacts：指定镜像是通过文件或者外部链接。
               最终是由heat调用相关接口使用该镜像并创建VDU。

..
  VDU1:
    type: tosca.nodes.nfv.VDU.Tacker
    artifacts:
      VNFImage:
        type: tosca.artifacts.Deployment.Image.VM
        file: http://download.cirros-cloud.net/0.3.5/ \
              cirros-0.3.5-x86_64-disk.img

3.6 VDU Capabilities

一个VDU的计算属性定义为capabilities。包括内存，磁盘、大页内存，cpu以及核数 每个核的线程数。 一个10GB磁盘，2GB内存，2核CPU，4 KB内存也可以定义如下：

..
  VDU1:
    type: tosca.nodes.nfv.VDU.Tacker
    capabilities:
      nfv_compute:
        properties:
          disk_size: 10 GB
          mem_size: 2048 MB
          num_cpus: 2
          mem_page_size: small
          cpu_allocation:
            cpu_affinity: dedicated
            thread_count: 4
            core_count: 2

3.7 更多属性

https://docs.openstack.org/tacker/latest/contributor/vnfd_template_description.html

4、Connection Points

    Connection Point在openstack中就是neutron的一个网络下的port。
    支持virtual NIC or a SR-IOV NIC。
    并且云主机内部网卡顺序会根据CP的定义来确定VDU网卡顺序。
    VL即virtual Link，为neutron的一个net。

..
topology_template:
  node_templates:
    VDU1:
      ..
    CP1:
      type: tosca.nodes.nfv.CP.Tacker
      properties:
        mac_address: fa:40:08:a0:de:0a
        ip_address: 10.10.1.12
        type: vnic
        anti_spoofing_protection: false
        management: true
        order: 0
        security_groups:
          - secgroup1
          - secgroup2
      requirements:
        - virtualLink:
            node: VL1
        - virtualBinding:
            node: VDU1
    CP2:
      type: tosca.nodes.nfv.CP.Tacker
      properties:
        type: vnic
        anti_spoofing_protection: false
        management: true
        order: 1
      requirements:
        - virtualLink:
            node: VL2
        - virtualBinding:
            node: VDU1
    VL1:
      ..
    VL2:
      ..

properties:

Name	Required	Type	Constraints	Description
type	No	String	One of vnic (default) sriov	Specifies the type of CP
anti_spoofing_protection	No	Boolean	None	Indicates whether anti_spoof rule is enabled for the VNF or not. Applicable only when CP type is virtual NIC
management	No	Boolean	None	Specifies whether the CP is accessible by the user or not
order	No	Integer	>= 0	Uniquely numbered order of CP within a VDU. Must be provided when binding more than one CP to a VDU and ordering is required.
security_groups	No	List	None	List of security groups to be associated with the CP
mac_address	No	String	None	The MAC address
ip _address	No	String	None	The IP address

5、Virtual Links

    Virtual link提供VDU的网络连通能力，是一个具体的网络实体。
    一个网络模板如下：

..
topology_template:
  node_templates:
    VDU1:
      ..
    CP1:
      ..
    VL1:
      type: tosca.nodes.nfv.VL
      properties:
        vendor: Acme
        network_name: net-01

6、Floating IP

   一个VDU挂载浮动IP的模板如下

..
topology_template:
  node_templates:
    VDU1:
      ..
    CP1:
      type: tosca.nodes.nfv.CP.Tacker
      properties:
        management: true
      requirements:
        - virtualLink:
            node: VL1
        - virtualBinding:
            node: VDU1
    VL1:
      ..
    FIP1:
      type: tosca.nodes.network.FloatingIP
      properties:
        floating_network: public
      requirements:
        - link:
            node: CP1

7、多VDU配置

    模板如下：

..
topology_template:
  node_templates:
    VDU1:
      ..
    VDU2:
      ..
    CP1:
      ..
    CP2:
      ..
    VL1:
      ..
    VL2:
      ..

8、小结

    一个VNFD定义了一个或多个VNF的拓扑结构。以下是一个比较全的模板：

tosca_definitions_version: tosca_simple_profile_for_nfv_1_0_0
description: Sample VNFD template mentioning possible values for each node.
metadata:
 template_name: sample-tosca-vnfd-template-guide
topology_template:
 node_templates:
   VDU:
     type: tosca.nodes.nfv.VDU.Tacker
     capabilities:
       nfv_compute:
         properties:
           mem_page_size: [small, large, any, custom]
           cpu_allocation:
             cpu_affinity: [shared, dedicated]
             thread_allocation: [avoid, separate, isolate, prefer]
             socket_count: any integer
             core_count: any integer
             thread_count: any integer
           numa_node_count: any integer
           numa_nodes:
             node0: [ id: >=0, vcpus: [host CPU numbers], mem_size: >= 0MB]
     properties:
       image: Image to be used in VM
       flavor: Nova supported flavors
       availability_zone: available availability zone
       mem_size: in MB
       disk_size: in GB
       num_cpus: any integer
       metadata:
         entry_schema:
       config_drive: [true, false]
       monitoring_policy:
         name: [ping, noop, http-ping]
         parameters:
           monitoring_delay: delay time
           count: any integer
           interval: time to wait between monitoring
           timeout: monitoring timeout time
           actions:
             [failure: respawn, failure: terminate, failure: log]
           retry: Number of retries
           port: specific port number if any
       config: Configuring the VDU as per the network function requirements
       mgmt_driver: [default=noop]
       service_type: type of network service to be done by VDU
       user_data: custom commands to be executed on VDU
       user_data_format: format of the commands
       key_name: user key
     artifacts:
       VNFImage:
         type: tosca.artifacts.Deployment.Image.VM
         file: file to be used for image
   CP:
     type: tosca.nodes.nfv.CP.Tacker
     properties:
       management: [true, false]
       anti_spoofing_protection: [true, false]
       type: [ sriov, vnic ]
       order: order of CP within a VDU
       security_groups: list of security groups
     requirements:
       - virtualLink:
          node: VL to link to
       - virtualBinding:
          node: VDU to bind to
   VL:
     type: tosca.nodes.nfv.VL
     properties:
       network_name: name of network to attach to
       vendor: Acme

9、参考文档
https://docs.openstack.org/tacker/latest/index.html
https://docs.openstack.org/tacker/latest/contributor/vnfd_template_description.html
https://github.com/openstack/tacker/blob/master/tacker/tosca/lib/tacker_nfv_defs.yaml