OSP的网络

0x00️⃣ 起因

事情的起因是，客户的场景没有ovnController, 并且结合了SRIOV/DPDK的场景。但是没有见过所以用此文记录一下其中的详情。

因为场景是RHOSO，首先要明确以下概念

Neutron network --+-- 东西流量 private network (tenant network) 
                  |
                  +-- 南北流量 provider network --+-- non-external provider network 
                                                 |
                                                 +-- external provider network

• 东西流量是指 instance-instance 流量
• 南北流量是指 instance-external 流量 — 本文重点

0x01️⃣ 北向中 OVN Controller 的工作类型

• 有ovnController — 连接instance需要通过OVN Gateway等组件转发到二层网络
• 无ovnController — 连接instance需要通过provider network例如BGP等二层网络

而进一步细分的话

neutron network --+-- private network (tenant network)
                  |
                  +-- provider network --+-- non-external provider network                 +-- ovnController -- physical network
                                         |                                  (vlan,flat) ---+
                                         +-- external provider network                     +-- physical network

1. 有ovnController

• OCP 节点作为OVN Gateway，则OVN controller需要运行在OCP节点
  

  https://docs.redhat.com/en/documentation/red_hat_openstack_services_on_openshift/18.0/html/configuring_networking_services/configuring-ovn-gateways_rhoso-cfgnet#ovn-gateway-ctrl-plane-dedicated-nic_configuring-gateways
  
  ovnController:
  
  spec:
    ...
  ovn:
    template:
      ovnController:
        networkAttachment: tenant
        nicMappings:
           <network_name: nic_name>

• 单独的networker node作为 OVN Gateway, 则需要额外部署Network nodes
  

  Chapter 5. Configuring Networker nodes | Configuring networking services | Red Hat OpenStack Services on OpenShift | 18.0 | Red Hat Documentation
  https://docs.redhat.com/en/documentation/red_hat_openstack_services_on_openshift/18.0/html/configuring_networking_services/configure-networker-nodes_rhoso-cfgnet#proc_creating-an-OpenStackDataPlaneNodeSet-CR-networker-preprovisioned_networkers
  
  
  apiVersion: dataplane.openstack.org/v1beta1
  kind: OpenStackDataPlaneNodeSet
  metadata:
    name: networker-nodes 
    namespace: openstack
  spec:
    env: 
      - name: ANSIBLE_FORCE_COLOR
        value: "True"

1. 无ovnController
   

   https://docs.redhat.com/en/documentation/red_hat_openstack_services_on_openshift/18.0/html/configuring_networking_services/configuring-ovn-gateways_rhoso-cfgnet#ovn-gateway-ctrlplane-none_configuring-gateways
   
   移除所有ovnController内容

0x02️⃣ 南向中 neutron 的使用

较为复杂的北向结构探讨完了，以下是南向的一些情况

neutron network --+-- private network (tenant network)                      1
                  | 
                  +-- provider network --+-- non-external provider network  2
                                         |                                 
                                         +-- external provider network      3

从上到下，创建它们的命令如下网络

[1]
openstack network create internal-network --internal

[2]
openstack network create public --provider-network-type vlan --provider-physical-network datacentre --provider-segment 104

[3]
openstack network create public --provider-network-type vlan --provider-physical-network datacentre --provider-segment 104 --external

0x03️⃣ 结语

对OVN的整体架构有了更深刻的认知。