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
