在Ubuntu18上搭建K8s集群(1.19.3）

淡淡的烟草味﹌ 2022-11-04 05:55 338阅读 0赞

## 环境准备 ##

为了演示简单，准备两台4GB内存,20GB硬盘的虚拟机，操作系统为ubuntu18.04-server

<table> 
 <thead> 
  <tr> 
   <th>角色</th> 
   <th>IP</th> 
   <th>HostName</th> 
  </tr> 
 </thead> 
 <tbody> 
  <tr> 
   <td>Master</td> 
   <td>192.168.47.144</td> 
   <td>master-k8s</td> 
  </tr> 
  <tr> 
   <td>Node</td> 
   <td>192.168.47.145</td> 
   <td>node1-k8s</td> 
  </tr> 
 </tbody> 
</table>

## 前置准备 ##

前置准备部分在master和node1都要分别执行：

1.  换源

sudo cp /etc/apt/sources.list /etc/apt/sources.list.bak

sudo vim /etc/apt/sources.list

# 阿里源
    deb http://mirrors.aliyun.com/ubuntu/ bionic main restricted universe multiverse
    deb http://mirrors.aliyun.com/ubuntu/ bionic-security main restricted universe multiverse
    deb http://mirrors.aliyun.com/ubuntu/ bionic-updates main restricted universe multiverse
    deb http://mirrors.aliyun.com/ubuntu/ bionic-proposed main restricted universe multiverse
    deb http://mirrors.aliyun.com/ubuntu/ bionic-backports main restricted universe multiverse
    deb-src http://mirrors.aliyun.com/ubuntu/ bionic main restricted universe multiverse
    deb-src http://mirrors.aliyun.com/ubuntu/ bionic-security main restricted universe multiverse
    deb-src http://mirrors.aliyun.com/ubuntu/ bionic-updates main restricted universe multiverse
    deb-src http://mirrors.aliyun.com/ubuntu/ bionic-proposed main restricted universe multiverse
    deb-src http://mirrors.aliyun.com/ubuntu/ bionic-backports main restricted universe multiverse

sudo apt update && sudo apt upgrade

1.  配置静态IP

设置root用户密码，并使用root用户登录

sudo passwd root
    su root

分别配置master和node1的静态ip：

vim /etc/netplan/00-installer-config.yaml

# master-k8s
    network:
        ethernets:
            ens33:
                addresses: [192.168.47.144/24]
                dhcp4: false
                gateway4: 192.168.47.2
                nameservers:
                    addresses: [192.168.47.2]
                optional: true
        version: 2

# node1-k8s
    network:
        ethernets:
            ens33:
                addresses: [192.168.47.145/24]
                dhcp4: false
                gateway4: 192.168.47.2
                nameservers:
                    addresses: [192.168.47.2]
                optional: true
        version: 2

应用刚才的修改

netplan apply

1.  修改hostname和host

vim /etc/hostname

vim /etc/hosts

添加以下两行（根据自己的ip和hostname修改）

192.168.47.144 master-k8s
    192.168.47.145 node1-k8s

重启机器使改动生效

1.  测试下两台虚拟机是否互通，是否能连网

cws@master-k8s:~$ ping 192.168.47.145
    PING 192.168.47.145 (192.168.47.145) 56(84) bytes of data.
    64 bytes from 192.168.47.145: icmp_seq=1 ttl=64 time=0.459 ms
    64 bytes from 192.168.47.145: icmp_seq=2 ttl=64 time=0.355 ms
    64 bytes from 192.168.47.145: icmp_seq=3 ttl=64 time=1.76 ms
    64 bytes from 192.168.47.145: icmp_seq=4 ttl=64 time=0.346 ms
    64 bytes from 192.168.47.145: icmp_seq=5 ttl=64 time=0.375 ms
    ^C
    --- 192.168.47.145 ping statistics ---
    5 packets transmitted, 5 received, 0% packet loss, time 4070ms
    rtt min/avg/max/mdev = 0.346/0.659/1.760/0.551 ms

cws@master-k8s:~$ ping www.baidu.com
    PING www.a.shifen.com (163.177.151.110) 56(84) bytes of data.
    64 bytes from 163.177.151.110 (163.177.151.110): icmp_seq=1 ttl=128 time=7.83 ms
    64 bytes from 163.177.151.110 (163.177.151.110): icmp_seq=2 ttl=128 time=8.11 ms
    64 bytes from 163.177.151.110 (163.177.151.110): icmp_seq=3 ttl=128 time=7.75 ms
    64 bytes from 163.177.151.110 (163.177.151.110): icmp_seq=4 ttl=128 time=8.01 ms
    64 bytes from 163.177.151.110 (163.177.151.110): icmp_seq=5 ttl=128 time=7.80 ms
    ^C
    --- www.a.shifen.com ping statistics ---
    5 packets transmitted, 5 received, 0% packet loss, time 4005ms
    rtt min/avg/max/mdev = 7.759/7.904/8.111/0.145 ms

1.  禁止交换分区

vim /etc/fstab

注释掉最后一行  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl8zNzU1MTAzNg_size_16_color_FFFFFF_t_70]

## 安装docker ##

安装docker也要分别在master和node1分别执行

> curl -fsSL https://get.docker.com | sudo sh -s -- --mirror Aliyun
    > sudo usermod -aG docker $USER
    > sudo mkdir -p /etc/docker
    > sudo tee /etc/docker/daemon.json <<-'EOF'
      {
        
      "exec-opts": ["native.cgroupdriver=systemd"],
      "log-driver": "json-file",
      "log-opts": {
        
          "max-size": "100m"
      },
      "storage-driver": "overlay2",
      "registry-mirrors": ["https://docker.mirrors.ustc.edu.cn/"]
      }
      EOF
    > sudo systemctl daemon-reload
    > sudo systemctl restart docker

检查docker是否安装成功

cws@master-k8s:~$ sudo docker run hello-world
    Unable to find image 'hello-world:latest' locally
    latest: Pulling from library/hello-world
    0e03bdcc26d7: Pull complete
    Digest: sha256:31b9c7d48790f0d8c50ab433d9c3b7e17666d6993084c002c2ff1ca09b96391d
    Status: Downloaded newer image for hello-world:latest
    
    Hello from Docker!
    This message shows that your installation appears to be working correctly.
    
    To generate this message, Docker took the following steps:
     1. The Docker client contacted the Docker daemon.
     2. The Docker daemon pulled the "hello-world" image from the Docker Hub.
        (amd64)
     3. The Docker daemon created a new container from that image which runs the
        executable that produces the output you are currently reading.
     4. The Docker daemon streamed that output to the Docker client, which sent it
        to your terminal.
    
    To try something more ambitious, you can run an Ubuntu container with:
     $ docker run -it ubuntu bash
    
    Share images, automate workflows, and more with a free Docker ID:
     https://hub.docker.com/
    
    For more examples and ideas, visit:
     https://docs.docker.com/get-started/

## 安装k8s ##

1.  安装k8s组件（分别在master和node1执行）

# 添加并信任APT证书
    > curl https://mirrors.aliyun.com/kubernetes/apt/doc/apt-key.gpg | sudo apt-key add -
    
    # 添加源地址
    > sudo add-apt-repository "deb https://mirrors.aliyun.com/kubernetes/apt/ kubernetes-xenial main"
    
    # 更新源并安装（可以改成自己需要的版本）
    > sudo apt update && sudo apt install -y kubeadm=1.19.3-00 kubectl=1.19.3-00 kubelet=1.19.3-00
    
    # 添加 completion
    > source <(kubectl completion bash)
    > source <(kubeadm completion bash)

1.  Master 节点启动  
    **这一步在master执行，注意修改成自己的ip**

sudo kubeadm init --apiserver-advertise-address 192.168.47.144 \
        --pod-network-cidr=10.244.0.0/16  \
        --image-repository registry.cn-hangzhou.aliyuncs.com/google_containers

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

记录输出的橙色框中内容，待会会用到  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl8zNzU1MTAzNg_size_16_color_FFFFFF_t_70 1]

1.  安装网络插件（Flannel 插件）  
    在master执行

# kubectl apply -f https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml
    # 这里这个网址被墙了，需要下载kube-flannel.yml到本地，或者找一个能访问的地址来替换
    # 我找到一个gitee上的可自行尝试：
    kubectl apply -f https://gitee.com/lm_py/kube-flannel.yaml/raw/master/kube-flannel.yml

1.  将node节点加入集群  
    **在node1**，执行前面我们记录下的代码，这里要用root登录

kubeadm join 192.168.47.144:6443 --token napprp.yj4u91sk5n1fq9ya \
    >     --discovery-token-ca-cert-hash sha256:4706f26a51a2303a2c79ea8137206d250450994bec9861ee3981cf934ae1ff89

1.  **在master上** 检查一下是否成功

cws@master-k8s:~$ kubectl get nodes
    NAME         STATUS   ROLES    AGE   VERSION
    master-k8s   Ready    master   14m   v1.19.3
    node1-k8s    Ready    <none>   96s   v1.19.3
    
    cws@master-k8s:~$ kubectl get pods -n kube-system
    NAME                                 READY   STATUS    RESTARTS   AGE
    coredns-6c76c8bb89-l8pz9             1/1     Running   0          17m
    coredns-6c76c8bb89-mv2lz             1/1     Running   0          17m
    etcd-master-k8s                      1/1     Running   0          17m
    kube-apiserver-master-k8s            1/1     Running   0          17m
    kube-controller-manager-master-k8s   1/1     Running   0          17m
    kube-flannel-ds-tzn5b                1/1     Running   0          11m
    kube-flannel-ds-x8n2w                1/1     Running   0          4m18s
    kube-proxy-8dwtc                     1/1     Running   0          17m
    kube-proxy-vz5jx                     1/1     Running   0          4m18s
    kube-scheduler-master-k8s            1/1     Running   0          17m
    
    cws@master-k8s:~$ kubectl get pods -A
    NAMESPACE     NAME                                 READY   STATUS    RESTARTS   AGE
    kube-system   coredns-6c76c8bb89-l8pz9             1/1     Running   0          93m
    kube-system   coredns-6c76c8bb89-mv2lz             1/1     Running   0          93m
    kube-system   etcd-master-k8s                      1/1     Running   0          93m
    kube-system   kube-apiserver-master-k8s            1/1     Running   0          93m
    kube-system   kube-controller-manager-master-k8s   1/1     Running   0          93m
    kube-system   kube-flannel-ds-tzn5b                1/1     Running   0          86m
    kube-system   kube-flannel-ds-x8n2w                1/1     Running   0          80m
    kube-system   kube-proxy-8dwtc                     1/1     Running   0          93m
    kube-system   kube-proxy-vz5jx                     1/1     Running   0          80m
    kube-system   kube-scheduler-master-k8s            1/1     Running   0          93m

到这里集群就搭建成功了

## 测试集群 ##

在Kubernetes集群中创建一个pod，验证是否正常运行：  
在master执行

$ kubectl create deployment nginx --image=nginx
    $ kubectl expose deployment nginx --port=80 --type=NodePort
    $ kubectl get pod,svc

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl8zNzU1MTAzNg_size_16_color_FFFFFF_t_70 2]  
片刻后，可以看到输出了端口号  
访问地址：http://NodeIP:Port，（我的是192.168.47.145:31984）  
可以看到nginx的欢迎页面，说明成功  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl8zNzU1MTAzNg_size_16_color_FFFFFF_t_70 3]

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[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl8zNzU1MTAzNg_size_16_color_FFFFFF_t_70 1]: /images/20221023/2aa7e25e30b74b0085e995edc4c983c2.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl8zNzU1MTAzNg_size_16_color_FFFFFF_t_70 2]: /images/20221023/8ab955c851744a3c90f9577f075c76cd.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl8zNzU1MTAzNg_size_16_color_FFFFFF_t_70 3]: /images/20221023/62244e063af040e5b5526cf399ee0b89.png