ubuntu20.04搭建k8s（1.26.3）

安装环境

Ubuntu20.04LTS Server

安装准备

一、设置固定IP

sudo -s # 切换root权限
vim /etc/netplan/00-installer-config.yaml
# 修改如下内容
# This is the network config written by 'subiquity'
network:
  ethernets:
    ens33:
      dhcp4: no #dhcp4关闭
      addresses: [192.168.0.128/24] #设置本机IP及掩码
      gateway4: 192.168.0.1 #设置网关
      nameservers:
          addresses: [114.114.114.114, 8.8.8.8] #设置DNS
  version: 2

sudo netplan apply # 应用

二、创建root用户

passwd root
sed -i 's/#PermitRootLogin prohibit-password/PermitRootLogin yes/' /etc/ssh/sshd_config
systemctl restart sshd

三、修改hostname（需要可以修改）

# 修改主机名
vim /etc/hostname
# 修改对应主机名
vim /etc/hosts
# 需要重启
reboot

四、关闭防火墙

systemctl stop ufw

五、关闭swap分区
临时关闭

swapoff -a

永久关闭

vim /etc/fstab   # 注释掉对应的一行，例如：  #/swapfile  none   swap  sw   0   0
echo "vm.swappiness = 0">> /etc/sysctl.conf
swapoff -a && swapon -a  #刷新SWAP
sysctl -p  #执行使其生效，不用重启系统

安装

切换root账号登陆
配置apt源

cp /etc/apt/sources.list /etc/apt/sources.list.bak
echo "" > /etc/apt/sources.list

cat << EOF >> /etc/apt/sources.list
deb http://mirrors.aliyun.com/ubuntu/ bionic main restricted universe multiverse
deb-src http://mirrors.aliyun.com/ubuntu/ bionic main restricted universe multiverse
deb http://mirrors.aliyun.com/ubuntu/ bionic-security main restricted universe multiverse
deb-src http://mirrors.aliyun.com/ubuntu/ bionic-security main restricted universe multiverse
deb http://mirrors.aliyun.com/ubuntu/ bionic-updates main restricted universe multiverse
deb-src http://mirrors.aliyun.com/ubuntu/ bionic-updates main restricted universe multiverse
deb http://mirrors.aliyun.com/ubuntu/ bionic-backports main restricted universe multiverse
deb-src http://mirrors.aliyun.com/ubuntu/ bionic-backports main restricted universe multiverse
deb http://mirrors.aliyun.com/ubuntu/ bionic-proposed main restricted universe multiverse
deb-src http://mirrors.aliyun.com/ubuntu/ bionic-proposed main restricted universe multiverse
deb https://mirrors.aliyun.com/kubernetes/apt kubernetes-xenial main

EOF

添加 Kubernetes 仓库的 GPG 密钥：

curl https://mirrors.aliyun.com/kubernetes/apt/doc/apt-key.gpg | sudo apt-key add -

更新apt源

apt update

安装依赖包

apt-get install -y apt-transport-https ca-certificates curl software-properties-common

安装kubeadm, kubelet 和 kubectl

apt install -y kubectl=1.26.3-00 kubelet=1.26.3-00 kubeadm=1.26.3-00

安装containerd

apt install -y containerd
mkdir -p /etc/containerd
containerd config default | sudo tee /etc/containerd/config.toml
systemctl restart containerd
apt-get install -y bridge-utils
modprobe br_netfilter
echo "net.ipv4.ip_forward = 1" | sudo tee -a /etc/sysctl.conf
sysctl -p

查看需要的镜像

kubeadm config images list # 执行这个命令，下面是结果

registry.k8s.io/kube-apiserver:v1.26.3                                                                                                                                                      
registry.k8s.io/kube-controller-manager:v1.26.3                                                                                                                                             
registry.k8s.io/kube-scheduler:v1.26.3                                                                                                                                                      
registry.k8s.io/kube-proxy:v1.26.3                                                                                                                                                          
registry.k8s.io/pause:3.9                                                                                                                                                                   
registry.k8s.io/etcd:3.5.6-0                                                                                                                                                                
registry.k8s.io/coredns/coredns:v1.9.3

这里有个坑是kubelet去启动的时候会去拉registry.k8s.io/pause:3.6的镜像，所以我在后面拉取镜像的时候把这个版本也拉了。

准备镜像
拉取

crictl -r unix:///run/containerd/containerd.sock pull registry.aliyuncs.com/google_containers/kube-apiserver:v1.26.3
crictl -r unix:///run/containerd/containerd.sock pull registry.aliyuncs.com/google_containers/kube-proxy:v1.26.3
crictl -r unix:///run/containerd/containerd.sock pull registry.aliyuncs.com/google_containers/kube-controller-manager:v1.26.3
crictl -r unix:///run/containerd/containerd.sock pull registry.aliyuncs.com/google_containers/kube-scheduler:v1.26.3
crictl -r unix:///run/containerd/containerd.sock pull registry.aliyuncs.com/google_containers/pause:3.9
crictl -r unix:///run/containerd/containerd.sock pull registry.aliyuncs.com/google_containers/pause:3.6
crictl -r unix:///run/containerd/containerd.sock pull registry.aliyuncs.com/google_containers/etcd:3.5.6-0
crictl -r unix:///run/containerd/containerd.sock pull registry.aliyuncs.com/google_containers/coredns:v1.9.3

tag镜像

ctr -n k8s.io images tag registry.aliyuncs.com/google_containers/kube-apiserver:v1.26.3 registry.k8s.io/kube-apiserver:v1.26.3
ctr -n k8s.io images tag registry.aliyuncs.com/google_containers/kube-proxy:v1.26.3 registry.k8s.io/kube-proxy:v1.26.3
ctr -n k8s.io images tag registry.aliyuncs.com/google_containers/kube-controller-manager:v1.26.3 registry.k8s.io/kube-controller-manager:v1.26.3
ctr -n k8s.io images tag registry.aliyuncs.com/google_containers/kube-scheduler:v1.26.3 registry.k8s.io/kube-scheduler:v1.26.3
ctr -n k8s.io images tag registry.aliyuncs.com/google_containers/pause:3.9 registry.k8s.io/pause:3.9
ctr -n k8s.io images tag registry.aliyuncs.com/google_containers/pause:3.6 registry.k8s.io/pause:3.6
ctr -n k8s.io images tag registry.aliyuncs.com/google_containers/etcd:3.5.6-0 registry.k8s.io/etcd:3.5.6-0
ctr -n k8s.io images tag registry.aliyuncs.com/google_containers/coredns:v1.9.3 registry.k8s.io/coredns/coredns:v1.9.3

查看镜像

crictl -r unix:///run/containerd/containerd.sock image

初始化 control-plane

kubeadm init --kubernetes-version=v1.26.3 --apiserver-advertise-address 192.168.0.128 --pod-network-cidr=10.244.0.0/16 --ignore-preflight-errors=Swap

记录下k8s join 的token，方便后续节点加入

kubeadm join 192.168.0.128:6443 --token {xxx}

加载环境变量

mkdir -p $HOME/.kube
cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
chown $(id -u):$(id -g) $HOME/.kube/config
export KUBECONFIG=/etc/kubernetes/admin.conf
echo "export KUBECONFIG=/etc/kubernetes/admin.conf" >> ~/.profile
source ~/.profile

部署网络插件

wget https://docs.projectcalico.org/v3.25/manifests/calico.yaml -O calico.yaml
kubectl apply -f calico.yaml

测试是否ok

kubectl get node

NAME     STATUS   ROLES           AGE     VERSION
master   Ready    control-plane   4m28s   v1.26.3

kubectl get pods -A

NAMESPACE     NAME                                      READY   STATUS    RESTARTS   AGE                                                                     
kube-system   calico-kube-controllers-57b57c56f-96sf7   1/1     Running   0          12m                                                                     
kube-system   calico-node-7mdrh                         1/1     Running   0          12m                                                                     
kube-system   coredns-787d4945fb-2chlh                  1/1     Running   0          16m                                                                     
kube-system   coredns-787d4945fb-lzdbt                  1/1     Running   0          16m                                                                     
kube-system   etcd-master                               1/1     Running   0          16m                                                                     
kube-system   kube-apiserver-master                     1/1     Running   0          16m                                                                     
kube-system   kube-controller-manager-master            1/1     Running   0          16m                                                                     
kube-system   kube-proxy-8z2bx                          1/1     Running   0          16m                                                                     
kube-system   kube-scheduler-master                     1/1     Running   0          16m

设置kubectl自动补全命令
安装bash-completion

apt-get install bash-completion

重新启动你的 shell 会话或者运行 source /etc/profile 以应用更改

echo 'source <(kubectl completion bash)' >>~/.bashrc
source ~/.bashrc