k8s内运行ubuntu容器

k8s内运行ubuntu镜像

环境

互相能访问的4台机器master,node01,node02,node03，4核心，内存8G

使用root操作

安装k8s

在master安装docker、kubeadm

添加kubernetes软件源:

在/etc/apt/sorce.list中添加一行：deb https://mirrors.aliyun.com/kubernetes/apt kubernetes-xenial main

添加秘钥 apt-key adv --recv-keys --keyserver keyserver.ubuntu.com 6A030B21BA07F4FB

更新

apt update

安装docker、kubeadm

apt install -y docker.io kubeadm

初始化k8s

查询需要下载的镜像：kubeadm config images list

比如1.17.0需要的是：

k8s.gcr.io/kube-apiserver:v1.17.0
k8s.gcr.io/kube-controller-manager:v1.17.0
k8s.gcr.io/kube-scheduler:v1.17.0
k8s.gcr.io/kube-proxy:v1.17.0
k8s.gcr.io/pause:3.1
k8s.gcr.io/etcd:3.4.3-0
k8s.gcr.io/coredns:1.6.5

利用国内的仓库下载需要的镜像：

  docker pull registry.cn-hangzhou.aliyuncs.com/google_containers/kube-apiserver:v1.17.0
  docker pull registry.cn-hangzhou.aliyuncs.com/google_containers/kube-controller-manager:v1.17.0
  docker pull registry.cn-hangzhou.aliyuncs.com/google_containers/kube-scheduler:v1.17.0
  docker pull registry.cn-hangzhou.aliyuncs.com/google_containers/kube-proxy:v1.17.0
  docker pull registry.cn-hangzhou.aliyuncs.com/google_containers/pause:3.1
  docker pull registry.cn-hangzhou.aliyuncs.com/google_containers/etcd:3.4.3-0
  docker pull registry.cn-hangzhou.aliyuncs.com/google_containers/coredns:1.6.5

将镜像打上标记，使k8s能识别：

docker tag registry.cn-hangzhou.aliyuncs.com/google_containers/pause:3.1 k8s.gcr.io/pause:3.1
  docker tag registry.cn-hangzhou.aliyuncs.com/google_containers/kube-apiserver:v1.17.0 k8s.gcr.io/kube-apiserver:v1.17.0
  docker tag registry.cn-hangzhou.aliyuncs.com/google_containers/kube-controller-manager:v1.17.0 k8s.gcr.io/kube-controller-manager:v1.17.0
  docker tag registry.cn-hangzhou.aliyuncs.com/google_containers/kube-scheduler:v1.17.0 k8s.gcr.io/kube-scheduler:v1.17.0
  docker tag registry.cn-hangzhou.aliyuncs.com/google_containers/kube-proxy:v1.17.0 k8s.gcr.io/kube-proxy:v1.17.0
  docker tag registry.cn-hangzhou.aliyuncs.com/google_containers/etcd:3.4.3-0 k8s.gcr.io/etcd:3.4.3-0
  docker tag registry.cn-hangzhou.aliyuncs.com/google_containers/coredns:1.6.5 k8s.gcr.io/coredns:1.6.5

关闭swap:swapoff -a

初始化k8s:kubeadm init

初始化成功的信息如下：

Your Kubernetes control-plane has initialized successfully!

To start using your cluster, you need to run the following as a regular user:

  mkdir -p $HOME/.kube
  sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
  sudo chown $(id -u):$(id -g) $HOME/.kube/config

You should now deploy a pod network to the cluster.
Run "kubectl apply -f [podnetwork].yaml" with one of the options listed at:
  https://kubernetes.io/docs/concepts/cluster-administration/addons/

Then you can join any number of worker nodes by running the following on each as root:

kubeadm join 192.168.8.61:6443 --token xh3fjq.f5kzistanapm6ar1 \
    --discovery-token-ca-cert-hash sha256:63c15d5be7a677165c7867187dd063dd5ed72b3d51c8f99b61a3efe3dade029b 

根据上面的提示，依次执行：

mkdir -p $HOME/.kube

sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config

sudo chown $(id -u):$(id -g) $HOME/.kube/config

然后在https://kubernetes.io/docs/concepts/cluster-administration/addons/选择一个网络插件，这里使用的是weave net。

添加weave net插件：

kubectl apply -n kube-system -f "https://cloud.weave.works/k8s/net?k8s-version=$(kubectl version | base64 | tr -d '\n')"

将节点加入到集群中

在每一个节点安装docker、kubeadm:

apt install docker.io kubeadm -y

在24小时内在节点执行master安装k8s后的提示信息，例如：

kubeadm join 192.168.8.61:6443 --token xh3fjq.f5kzistanapm6ar1 \ --discovery-token-ca-cert-hash sha256:63c15d5be7a677165c7867187dd063dd5ed72b3d51c8f99b61a3efe3dade029b

在master下查看node的加入情况：

root@desktop:~# kubectl get node
NAME      STATUS     ROLES    AGE    VERSION
desktop   Ready      master   125m   v1.17.0
node01    Ready      <none>   117m   v1.17.0
node02    NotReady   <none>   116m   v1.17.0
node03    Ready      <none>   104m   v1.17.0

如果状态是NotReady,可能是节点没有禁用swap。

安装dashboard

使用yaml安装dashboard：

kubectl apply -f https://raw.githubusercontent.com/kubernetes/dashboard/v2.0.0-beta5/aio/deploy/recommended.yaml

创建 ServiceAccount 和 ClusterRoleBinding，创建一个 auth.yaml，内容如下:

apiVersion: v1
kind: ServiceAccount
metadata:
  name: admin-user
  namespace: kubernetes-dashboard

---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
  name: admin-user
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: cluster-admin
subjects:
- kind: ServiceAccount
  name: admin-user
  namespace: kubernetes-dashboard

执行 kubectl apply -f auth.yaml

获得token：

kubectl -n kubernetes-dashboard describe secret $(kubectl -n kubernetes-dashboard get secret | grep admin-user | awk '{print $1}')

输出的信息如下：

root@desktop:~# kubectl -n kubernetes-dashboard describe secret $(kubectl -n kubernetes-dashboard get secret | grep admin-user | awk '{print $1}')
Name:         admin-user-token-vpr7v
Namespace:    kubernetes-dashboard
Labels:       <none>
Annotations:  kubernetes.io/service-account.name: admin-user
              kubernetes.io/service-account.uid: f44f954e-581c-4b9f-88a7-98e566442ed8

Type:  kubernetes.io/service-account-token

Data
====
ca.crt:     1025 bytes
namespace:  20 bytes
token:      eyJhbGciOiJSUzI1NiIsImtpZCI6Ik41c1ZnR2tIRU4tNktOQV84YzQ0UUNGZzhQRHZPZENsRjkza21iejQ4M2MifQ.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.a3Bj81-2xIHsSJ0isP6qXjmpazJmh1bkn3tjaQefOmrLUmgmnrEsDMobeD-6YasJ0i4Iq69hT8ITWRr5XyZ1MZx7ueGwsqdGzYQIgnGS5xIUISi7sJjRQ_K9aoh29WaL4WBBkiOQb8xBOShH7-Lp72a6EqZnko5UkorolLNJzquow27sDc4gcB-c8wRs_bl2hD-BuraPremQlBhleKgsab49xUWjgE45GYIW46nzmqwPTl-B6MBUNyj442WrHecf7Yy50mgf6lXFVHzkHaHjcWH3OfgKu7GV3WBoc0K6oLen2R5awYmJe31sLcoFFBp64MRfbhO3kGGRboXTqRUeEQ

记录下token，以便登录bashboard。

启动proxy:

kubectl procy

然后登录 dashboard，使用token方式登录：

运行ubuntu镜像

下载镜像

每一个节点都需要下载ubuntu：

docker pull ubuntu

编写yaml

myubuntu.yaml如下：

apiVersion: v1
kind: Pod
metadata:
 #Pod的名称，全局唯一
 name: myubuntu
 labels:
  name: myubuntu
spec:
  #设置存储卷
  volumes:
   - name: myubuntulogs
     hostPath:
      path: /home/user/myubuntu
  containers:
   #容器名称
   - name: myubuntu
     #容器对应的Docker Image
     image: ubuntu
     command: [ "/bin/bash", "-c", "--" ]
     args: [ "while true; do sleep 3600; done;" ]
     volumeMounts:
      - mountPath: /mydata-log
        name: myubuntulogs

创建pod:kubectl apply -f myubuntu.yaml

打开dashboard，选择Pod->myubuntu ,右键点击exec，在dashboard进入ubuntu容器：

检查网络设置：

在容器内下载常用的网络工具：

apt install net-tools inetutils-ping -y

检查路由：

root@myubuntu:/# route
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
default         10.44.0.0       0.0.0.0         UG    0      0        0 eth0
10.32.0.0       0.0.0.0         255.240.0.0     U     0      0        0 eth0

特别感谢yytlmm博主