kubernets 集群安装部署(kubeadm)

安装部署

安装前准备

  1. 设置每个机器自己的hostname

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    hostnamectl set-hostname xxx

  2. 关闭seLinux

  3. 关闭​​swap​​分区

这个安装系统的时候就没有设置交换分区

  1. 允许 iptables 检查桥接流量
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# 设置加载br_netfilter模块
cat <<EOF | sudo tee /etc/modules-load.d/k8s.conf
overlay
br_netfilter
EOF

sudo modprobe overlay
sudo modprobe br_netfilter
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# 开启bridge-nf-call-iptables ，设置所需的 sysctl 参数，参数在重新启动后保持不变 
# 参考：https://imroc.cc/post/202105/why-enable-bridge-nf-call-iptables/

cat <<EOF | sudo tee /etc/sysctl.d/k8s.conf
net.bridge.bridge-nf-call-iptables  = 1
net.bridge.bridge-nf-call-ip6tables = 1
net.ipv4.ip_forward                 = 1
EOF

# 应用 sysctl 参数而不重新启动
sudo sysctl --system

安装 containerd

安装容器运行时

在所有主机上安装容器运行时，推荐使用 containerd

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# for centos
yum install -y yum-utils

yum-config-manager --add-repo https://download.docker.com/linux/centos/docker-ce.repo

yum install -y containerd.io

生成默认配置

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containerd config default > /etc/containerd/config.toml

修改CgroupDriver为systemd， k8s官方推荐使用systemd类型的CgroupDriver。

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[plugins."io.containerd.grpc.v1.cri".containerd.runtimes.runc]
  ...
  [plugins."io.containerd.grpc.v1.cri".containerd.runtimes.runc.options]
    SystemdCgroup = true

修改 pause 镜像地址为国内的。

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sandbox_image = "registry.aliyuncs.com/k8sxio/pause:3.6"

重启containerd，设置开机自启动

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systemctl enable containerd
systemctl restart containerd

安装 kubeadm,kubelet,kubectl

在所有主机上安装kubeadm，kubelet，kubectl。最好版本与需要安装的k8s的版本一致。

准备 国内 yum 源

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[kubernetes]
name=Kubernetes
baseurl=https://mirrors.aliyun.com/kubernetes/yum/repos/kubernetes-el7-x86_64/
enabled=1
gpgcheck=0
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yum install kubeadm kubelet kubectl
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systemctl enable kubelet
systemctl restart kubelet

systemctl enable --now kubelet # 此时启动kubelet会失败，只有执行kubeadm init 成功之后这个服务才能成功启动。

初始化master节点

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kubeadm init \
--apiserver-advertise-address=<master 节点IP，也是apiserver的IP> \
--control-plane-endpoint=k8s-master \
--image-repository registry.cn-hangzhou.aliyuncs.com/lfy_k8s_images \
--kubernetes-version v1.20.9 \
--service-cidr=10.96.0.0/16 \
--pod-network-cidr=10.244.0.0/16

安装网络插件

执行如下命令部署 flannel：

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kubectl apply -f https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml

初始化worker节点

其他参考

https://blog.51cto.com/foxhound/2517491

kubeadm-config 支持以下配置类型

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apiVersion: kubeadm.k8s.io/v1beta2
kind: InitConfiguration

apiVersion: kubeadm.k8s.io/v1beta2
kind: ClusterConfiguration

apiVersion: kubelet.config.k8s.io/v1beta1
kind: KubeletConfiguration

apiVersion: kubeproxy.config.k8s.io/v1alpha1
kind: KubeProxyConfiguration

apiVersion: kubeadm.k8s.io/v1beta2
kind: JoinConfiguration

https://k8s.huweihuang.com/project/setup/installer/install-k8s-by-kubeadm

问题合集

问题1： kubeadm init 时候 apiserver 不能配置成域名，只能是IP地址

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[root@k8s-master ~]# kubeadm init --config init-config.yaml --v=5
I0728 14:34:52.451879    2833 initconfiguration.go:255] loading configuration from "init-config.yaml"
couldn't use "apiserver.magesfc.com" as "apiserver-advertise-address", must be ipv4 or ipv6 address
k8s.io/kubernetes/cmd/kubeadm/app/util/config.SetAPIEndpointDynamicDefaults
        cmd/kubeadm/app/util/config/initconfiguration.go:135
k8s.io/kubernetes/cmd/kubeadm/app/util/config.SetInitDynamicDefaults
        cmd/kubeadm/app/util/config/initconfiguration.go:67
k8s.io/kubernetes/cmd/kubeadm/app/util/config.documentMapToInitConfiguration
        cmd/kubeadm/app/util/config/initconfiguration.go:369
k8s.io/kubernetes/cmd/kubeadm/app/util/config.BytesToInitConfiguration
        cmd/kubeadm/app/util/config/initconfiguration.go:290
k8s.io/kubernetes/cmd/kubeadm/app/util/config.LoadInitConfigurationFromFile
        cmd/kubeadm/app/util/config/initconfiguration.go:262
k8s.io/kubernetes/cmd/kubeadm/app/util/config.LoadOrDefaultInitConfiguration
        cmd/kubeadm/app/util/config/initconfiguration.go:274
k8s.io/kubernetes/cmd/kubeadm/app/cmd.newInitData
        cmd/kubeadm/app/cmd/init.go:304
k8s.io/kubernetes/cmd/kubeadm/app/cmd.newCmdInit.func3
        cmd/kubeadm/app/cmd/init.go:157
k8s.io/kubernetes/cmd/kubeadm/app/cmd/phases/workflow.(*Runner).InitData
        cmd/kubeadm/app/cmd/phases/workflow/runner.go:183
k8s.io/kubernetes/cmd/kubeadm/app/cmd.newCmdInit.func1
        cmd/kubeadm/app/cmd/init.go:103
github.com/spf13/cobra.(*Command).execute
        vendor/github.com/spf13/cobra/command.go:916
github.com/spf13/cobra.(*Command).ExecuteC
        vendor/github.com/spf13/cobra/command.go:1040
github.com/spf13/cobra.(*Command).Execute
        vendor/github.com/spf13/cobra/command.go:968
k8s.io/kubernetes/cmd/kubeadm/app.Run
        cmd/kubeadm/app/kubeadm.go:50
main.main
        cmd/kubeadm/kubeadm.go:25
runtime.main
        /usr/local/go/src/runtime/proc.go:250
runtime.goexit
        /usr/local/go/src/runtime/asm_amd64.s:1598
[root@k8s-master ~]#