【kubeedge概念】kubeedge架构与部署安装

Abstract

kubeedge 组件    

Edged：一个运行在 edge 节点的 agent 程序，管理边缘的容器化应用程序

EdgeHub：边缘的通信接口模块。这是一个 Web 套接字客户端，负责边缘计算与云服务的交互。包括同步云端资源到边缘端，以及报告边缘端 host 和 device 状态到云端 

CloudHub：云端通讯接口模块。一个 Web 套接字服务器，负责监视云端的更改、缓存以及向 EdgeHub 发送消息

EdgeController：管理边缘节点。它是一个扩展的 Kubernetes 控制器，管理边缘节点和 pod 元数据，以便数据可以面向特定的边缘节点

EventBus：使用 MQTT 处理内部边缘通信。MQTT 客户端与 MQTT 服务器（mosquitto）交互，为其他组件提供发布和订阅功能

DeviceTwin：处理设备元数据的设备软件镜像。该模块有助于处理设备状态并将其同步到云上。它还为应用程序提供查询接口，它连接到一个轻量级数据库（SQLite）

MetaManager：管理边缘节点上的元数据。这是 Edged 和 Edgehub 之间的消息处理器。负责在轻量级数据库（SQLite）中存储 / 检索元数据

 

      kubeEdge 包括 cloud 和 edge 部分，在 kubernetes 构建，在 cloud 与  edge 端提供核心的基础支持，比如网络，应用，部署以及元数据的同步等。

      安装kubeEdge 需要安装 kubernetes 集群，cloud 与 edge 部分

• cloud side： docker, kubernetes cluster and cloudcore.
• edge side：docker, mqtt and edgecore.

Prerequisites

• Install docker on cloud and edge side （you can also run other runtime, such as containerd）

• Install kubeadm/kubectl on cloud side

• Creating kubernetes cluster with kubeadm on cloud side

• Go The minimum required go version is 1.12. You can install this version by using this website.

• Install mosquitto on every edge side

 

1.  安装 cloud side

git clone https://github.com/kubeedge/kubeedge.git $GOPATH/src/github.com/kubeedge/kubeedge
cd $GOPATH/src/github.com/kubeedge/kubeedge

   1.1 生成证书

      KubeEdge 需要 RootCA 证书和一个证书/密钥对。cloud 和 edge 端都可以使用相同的证书/密钥对

$GOPATH/src/github.com/kubeedge/kubeedge/build/tools/certgen.sh genCertAndKey edge

     /etc/kubeedge/ca 和 /etc/kubeedge/certs 生成，可以拷贝至 edge 服务端

   1.2 编译 cloudcore

cd $GOPATH/src/github.com/kubeedge/kubeedge/
make all WHAT=cloudcore

   1.3 创建设备模块和设备CRD

cd $GOPATH/src/github.com/kubeedge/kubeedge/build/crds/devices
kubectl create -f devices_v1alpha1_devicemodel.yaml
kubectl create -f devices_v1alpha1_device.yaml

   1.4 cloudcore 可执行文件和配置文件

cd $GOPATH/src/github.com/kubeedge/kubeedge/cloud
# run edge controller
# `conf/` should be in the same directory as the cloned KubeEdge repository
# verify the configurations before running cloud(cloudcore)
mkdir -p /opt/kubeedge/conf
cp cloudcore /opt/kubeedge
cp -rf conf/* /opt/kubeedge/conf/

     1.4.1 controller.yaml 内容

controller:
  kube:
    master:     # kube-apiserver address (such as:http://localhost:8080)
    content_type: "application/vnd.kubernetes.protobuf"
    qps: 5
    burst: 10
    node_update_frequency: 10
    kubeconfig: "~/.kube/config"   #Enter path to kubeconfig file to enable https connection to k8s apiserver, if master and kubeconfig are both set, master will override any value in kubeconfig.
cloudhub:
  protocol_websocket: true # enable websocket protocol
  port: 10000 # open port for websocket server
  protocol_quic: true # enable quic protocol
  quic_port: 10001 # open prot for quic server
  max_incomingstreams: 10000 # the max incoming stream for quic server
  enable_uds: true # enable unix domain socket protocol
  uds_address: unix:///var/lib/kubeedge/kubeedge.sock # unix domain socket address
  address: 0.0.0.0
  ca: /etc/kubeedge/ca/rootCA.crt
  cert: /etc/kubeedge/certs/edge.crt
  key: /etc/kubeedge/certs/edge.key
  keepalive-interval: 30
  write-timeout: 30
  node-limit: 10
devicecontroller:
  kube:
    master:        # kube-apiserver address (such as:http://localhost:8080)
    content_type: "application/vnd.kubernetes.protobuf"
    qps: 5
    burst: 10
    kubeconfig: "~/.kube/config" #Enter path to kubeconfig file to enable https connection to k8s apiserver,if master and kubeconfig are both set, master will override any value in kubeconfig.

   1.5 运行 cloudcore

    简单粗暴运行 nohup ./cloudcore &

     1.5.1 可以使用 systemd 挂历 cloudcore服务

sudo ln build/tools/cloudcore.service /etc/systemd/system/cloudcore.service
sudo systemctl daemon-reload
sudo systemctl start cloudcore

  

2. 部署 edge 端服务

       kube edge 提供了示例 node.json 在 kubernetes 中添加一个节点。请确保在Kubernetes中添加了Edge节点。运行以下步骤以添加边缘节点

       $GOPATH/src/github.cbiom/kubeedge/kubeedge/build/node.json 更改 metadata.name 为自己的边缘节点名称

   2.1 编译 edgecore

cd $GOPATH/src/github.com/kubeedge/kubeedge
make all WHAT=edgecore

   2.2 配置 edgecore

     # cat /opt/kubeedge/conf/edge.yaml

mqtt:
    server: tcp://127.0.0.1:1883 # external mqtt broker url.
    internal-server: tcp://127.0.0.1:1884 # internal mqtt broker url.
    mode: 0 # 0: internal mqtt broker enable only. 1: internal and external mqtt broker enable. 2: external mqtt broker
enable only.
    qos: 0 # 0: QOSAtMostOnce, 1: QOSAtLeastOnce, 2: QOSExactlyOnce.
    retain: false # if the flag set true, server will store the message and can be delivered to future subscribers.
    session-queue-size: 100 # A size of how many sessions will be handled. default to 100.

edgehub:
    websocket:
        url: wss://0.0.0.0:10000/e632aba927ea4ac2b575ec1603d56f10/edge-node/events 
        certfile: /etc/kubeedge/certs/edge.crt
        keyfile: /etc/kubeedge/certs/edge.key
        handshake-timeout: 30 #second
        write-deadline: 15 # second
        read-deadline: 15 # second
    quic:
        url: 127.0.0.1:10001
        cafile: /etc/kubeedge/ca/rootCA.crt
        certfile: /etc/kubeedge/certs/edge.crt
        keyfile: /etc/kubeedge/certs/edge.key
        handshake-timeout: 30 #second
        write-deadline: 15 # second
        read-deadline: 15 # second
    controller:
        protocol: websocket # websocket, quic
        heartbeat: 15  # second
        project-id: e632aba927ea4ac2b575ec1603d56f10
        node-id: edge-node

edged:
    register-node-namespace: default
    hostname-override: edge-node
    interface-name: eth0
    edged-memory-capacity-bytes: 7852396000
    node-status-update-frequency: 10 # second
    device-plugin-enabled: false
    gpu-plugin-enabled: false
    image-gc-high-threshold: 80 # percent
    image-gc-low-threshold: 40 # percent
    maximum-dead-containers-per-container: 1
    docker-address: unix:///var/run/docker.sock
    runtime-type: docker
    remote-runtime-endpoint: unix:///var/run/dockershim.sock
    remote-image-endpoint: unix:///var/run/dockershim.sock
    runtime-request-timeout: 2
    podsandbox-image: kubeedge/pause:3.1 # kubeedge/pause:3.1 for x86 arch , kubeedge/pause-arm:3.1 for arm arch, kubeedge/pause-arm64 for arm64 arch
    image-pull-progress-deadline: 60 # second
    cgroup-driver: cgroupfs
    node-ip: ""
    cluster-dns: ""
    cluster-domain: ""

    mesh:
        loadbalance:
            strategy-name: RoundRobin

   2.3 运行 edgecore

cp $GOPATH/src/github.com/kubeedge/kubeedge/edge/edgecore /opt/kubeedge
cd /opt/kubeedge
./edgecore
# or
nohup ./edgecore > edgecore.log 2>&1 &

   2.4 以 systemd 运行 edgecore

sudo ln build/tools/edgecore.service /etc/systemd/system/edgecore.service
sudo systemctl daemon-reload
sudo systemctl start edgecore

 

3. 验证测试

kubectl apply -f $GOPATH/src/github.com/kubeedge/kubeedge/build/deployment.yaml

 

参考：

     https://github.com/kubeedge/kubeedge

     https://docs.kubeedge.io/en/latest/setup/setup.html