# k8s之安装与配置_单机_二进制
## 环境

|  | 说明 |
| --- | --- |
| 操作系统 | CentOS Linux release 7.7.1908 (Core) |
| Docker | 18.06.3-ce | 
| Kubernetes | v1.16.2 | 
| Etcd | v3.3.15 | 

## 主机规划

| 主机名 | IP | 角色 | 安装应用 |
| --- | --- | --- | --- |
| k8s-demo3 | 192.168.206.117 | master | kube-apiserver/kube-scheduler/kube-controller-manager/etcd | 
| k8s-demo3 | 192.168.206.117 | node | docker/kubelet/kube-proxy | 

> 注: 以上为了说明master和node安装的应用区别才分开写,单机安装所有应用安装一起。

## 下载
**非常重要: 下载安装包前请阅读 https://kubernetes.io/docs/setup/release/notes/#dependencies**

##### 下载docker离线安装包

https://download.docker.com/linux/static/stable/x86_64/

![image.jpg](images/docker_download.png)

##### 下载k8s 

https://github.com/kubernetes/kubernetes/blob/master/CHANGELOG-1.16.md#downloads-for-v1162

![image.jpg](https://github.com/osoctz/k8s-learning/blob/master/images/k8s.png)

##### 下载etcd

https://github.com/etcd-io/etcd/releases/tag/v3.3.15

![image.jpg](https://github.com/osoctz/k8s-learning/blob/master/images/etcd.png)

##### 下载flanneld
https://github.com/coreos/flannel/releases
![image.jpg](https://github.com/osoctz/k8s-learning/blob/master/images/flanneld_dl.png)

## 安装前环境初始化

    #防火墙
    systemctl stop firewalld
    systemctl disable firewalld
    #selinux
    vi /etc/selinux/config
    将SELINUX=enforcing改为SELINUX=disabled，wq保存退出

    #关闭swap
    swapoff -a
    vi /etc/fstab
    将swap那一行注释掉

    #目录初始化
    mkdir -p /etc/etcd/
    mkdir -p /var/lib/etcd/
    mkdir -p /etc/kubernetes/
    mkdir -p /var/log/kubernetes/
    mkdir -p /var/lib/kubelet/

    #hosts
    echo "127.0.0.1   $(hostname)" >> /etc/hosts
    
## 安装Docker

    chmod +x ~/install_docker.sh
    ~/install_docker.sh docker-18.06.3-ce.tgz

## 部署 Master&Node 服务

    # 安装命令
    tar -zxvf kubernetes-server-linux-amd64.tar.gz
    cp ~/kubernetes/server/bin/{kube-apiserver,kube-controller-manager,kube-scheduler,kubectl,kube-proxy,kubelet} /usr/bin/
    tar -zxvf etcd-v3.3.15-linux-amd64.tar.gz
    cp ~/etcd-v3.3.15-linux-amd64/{etcd,etcdctl} /usr/bin/

##### etcd安装
    #系统服务配置
    cat>/usr/lib/systemd/system/etcd.service<<EOF
        [Unit]
        Description=etcd.service
        [Service]
        Type=notify
        TimeoutStartSec=0
        Restart=always
        WorkingDirectory=/var/lib/etcd
        ExecStart=/usr/bin/etcd \
        --name=ETCDServer \
        --data-dir=/var/lib/etcd/ \
        --listen-client-urls=http://0.0.0.0:2379 \
        --advertise-client-urls=http://192.168.206.117:2379 
        [Install]
        WantedBy=multi-user.target
    EOF

    # 启动服务
    systemctl daemon-reload
    systemctl enable etcd.service --now
    etcdctl cluster-health
    
    
![image.jpg](https://github.com/osoctz/k8s-learning/blob/master/images/etcd/etcd-status.png)

##### kube-apiserver安装

    #系统服务配置 
    cat>/usr/lib/systemd/system/kube-apiserver.service<<EOF
    [Unit]
    Description=Kubernetes API Server
    After=etcd.service
    Wants=etcd.service
    [Service]
    #EnvironmentFile=/etc/kubernetes/apiserver
    ExecStart=/usr/bin/kube-apiserver  \
    --etcd-servers=http://192.168.206.117:2379 \
    --insecure-bind-address=0.0.0.0 \
    --port=8080 \
    --service-cluster-ip-range=10.2.0.0/16 \
    --admission-control=NamespaceLifecycle,NamespaceExists,LimitRanger,ServiceAccount,DefaultStorageClass,ResourceQuota
    Restart=on-failure
    Type=notify
    LimitNOFILE=65536
    [Install]
    WantedBy=multi-user.target
    EOF

    #启动服务
    systemctl daemon-reload
    systemctl enable kube-apiserver.service --now
    systemctl status kube-apiserver.service
    
![image.jpg](https://github.com/osoctz/k8s-learning/blob/master/images/apiserver/apiserver-status.jpg)

##### kube-controller-manager安装

    #系统服务配置 
    cat>/usr/lib/systemd/system/kube-controller-manager.service<<EOF
    [Unit]
    Description=Kubernetes Controller Manager
    After=kube-apiserver.service
    Requires=kube-apiserver.service
    [Service]
    #EnvironmentFile=-/etc/kubernetes/controller-manager
    ExecStart=/usr/bin/kube-controller-manager \
    --master=http://192.168.206.117:8080 \
    --service-cluster-ip-range=10.2.0.0/16
    Restart=on-failure
    LimitNOFILE=65536
    [Install]
    WantedBy=multi-user.target
    EOF

    #启动服务
    systemctl daemon-reload
    systemctl enable kube-controller-manager.service --now
    systemctl status kube-controller-manager.service
    
    
![image.jpg](https://github.com/osoctz/k8s-learning/blob/master/images/controller/kube-controller-manager-status.png)

##### kube-scheduler安装
    #系统服务配置 
    cat>/usr/lib/systemd/system/kube-scheduler.service<<EOF
    [Unit]
    Description=Kubernetes Scheduler
    After=kube-apiserver.service
    Requires=kube-apiserver.service
    [Service]
    User=root
    #EnvironmentFile=/etc/kubernetes/scheduler
    ExecStart=/usr/bin/kube-scheduler --master=http://192.168.206.117:8080
    Restart=on-failure
    LimitNOFILE=65536
    [Install]
    WantedBy=multi-user.target
    EOF

    #启动服务
    systemctl daemon-reload
    systemctl enable kube-scheduler.service --now
    systemctl status kube-scheduler.service
    
    
![image.jpg](https://github.com/osoctz/k8s-learning/blob/master/images/scheduler/scheduler-status.png)

##### kube-proxy安装
    #系统服务配置 
    cat>/usr/lib/systemd/system/kube-proxy.service<<EOF
    [Unit]
    Description=Kubernetes Kube-Proxy Server
    Documentation=https://github.com/GoogleCloudPlatform/kubernetes
    After=network.target
    Requires=network.service
    [Service]
    #EnvironmentFile=/etc/kubernetes/proxy
    ExecStart=/usr/bin/kube-proxy --master=http://192.168.206.117:8080
    Restart=on-failure
    LimitNOFILE=65536
    [Install]
    WantedBy=multi-user.target
    EOF

    #启动服务
    systemctl daemon-reload
    systemctl enable kube-proxy.service --now
    systemctl status kube-proxy.service
    
    
![image.jpg](https://github.com/osoctz/k8s-learning/blob/master/images/proxy/kube-proxy-status.png)

##### kubelet安装
    #系统服务配置 
    cat>/usr/lib/systemd/system/kubelet.service<<EOF
    [Unit]
    Description=Kubernetes Kubelet Server
    Documentation=https://github.com/GoogleCloudPlatform/kubernetes
    After=docker.service
    Requires=docker.service
    [Service]
    WorkingDirectory=/var/lib/kubelet
    EnvironmentFile=/etc/kubernetes/kubelet
    ExecStart=/usr/bin/kubelet \
    --address=0.0.0.0 \
    --pod-infra-container-image=registry.cn-hangzhou.aliyuncs.com/google_containers/pause:3.1 \
    --enable-server=true \
    --enable-debugging-handlers=true \
    --fail-swap-on=false \
    --kubeconfig=/var/lib/kubelet/kubeconfig
    Restart=on-failure
    KillMode=process
    [Install]
    WantedBy=multi-user.target
    EOF

    #kubeconfig配置  
    cat>/var/lib/kubelet/kubeconfig<<EOF
    apiVersion: v1
    kind: Config
    users:
    - name: kubelet
    clusters:
    - name: kubernetes
      cluster:
        server: http://192.168.206.117:8080
    contexts:
    - context:
        cluster: kubernetes
        user: kubelet
      name: default
    current-context: default
    EOF


    #加载/etc/kubernetes/kubelet中需要的docker镜像
    docker load -i ~/pause-amd64.tar
    
       
    #启动服务
    swapoff -a
    systemctl daemon-reload
    systemctl enable kubelet.service --now
    systemctl status kubelet.service
    
![image.jpg](images/kubelet/kubelet-status.png)

##### 验证
![image.jpg](images/check.png)

## 问题解决
>问题1: 创建POD,kube-controller-manager组件提示“No API token found for service account "default", retry after the token is automatically created and added to the service account”

##### 解决方法
    #首先生成密钥
    openssl genrsa -out /etc/kubernetes/serviceaccount.key 2048
    #kube-apiserver添加参数
    KUBE_API_ARGS="--service_account_key_file=/etc/kubernetes/serviceaccount.key"
    #kube-controller-manager添加参数
    KUBE_CONTROLLER_MANAGER_ARGS="--service_account_private_key_file=/etc/kubernetes/serviceaccount.key"
    
>问题2: 创建POD后 kubectl describe 查看提示"kubelet does not have ClusterDNS IP configured and cannot create Pod using "ClusterFirst" policy. Falling back to "Default" policy"

##### 解决方法
    #kubelet添加参数
    --hostname-override=all