centos搭建kubernetes集群步骤

[1. 修改host](#1. 修改host)

[2. 时间同步](#2. 时间同步)

[3. 禁用firewalled](#3. 禁用firewalled)

[4. 禁用selinux](#4. 禁用selinux)

[5. 禁用swap](#5. 禁用swap)

[6. 网桥设置](#6. 网桥设置)

[7. docker安装](#7. docker安装)

[8. 安装k8s](#8. 安装k8s)

[9. 异性操作](#9. 异性操作)

[10. 配置flannel](#10. 配置flannel)

1. 修改host

bash 复制代码

cat >> /etc/hosts << EOF
172.16.188.175 master
172.16.188.176 node1
172.16.188.177 node2 
EOF

cat /etc/hosts

2. 时间同步

bash 复制代码

systemctl start chronyd && systemctl enable chronyd
date

3. 禁用firewalled

bash 复制代码

systemctl stop firewalld && systemctl disable firewalld

4. 禁用selinux

bash 复制代码

setenforce 0 && sed -i 's/ASELINUX=,*/SELINUX=disabled/' /etc/selinux/config

5. 禁用swap

临时关闭，重启失效

bash 复制代码

swapoff -a

永久关闭

bash 复制代码

swapoff -a && sed -i '/ swap / s/^\(.*\)$/# \1/g' /etc/fstab

默认情况下，K8s为了追求高性能，不建议使用交换分区，为此它要求每个节点禁用swap，否则各个节点中的kubelet无法运行

6. 网桥设置

bash 复制代码

cat > /etc/sysctl.d/kubernetes.conf << EOF
net.bridge.bridge-nf-call-ip6tables = 1
net.bridge.bridge-nf-call-iptables = 1
net.ipv4.ip_forward = 1
EOF

sysctl --system

7. docker安装

bash 复制代码

yum-config-manager --add-repo http://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo

yum makecache fast

yum -y install docker-ce

systemctl enable docker&& systemctl start docker

docker -v

设置daemon.json

bash 复制代码

mkdir -p /etc/docker

tee /etc/docker/daemon.json <<-'EOF'
{
  "exec-opts":["native.cgroupdriver=systemd"],
	"registry-mirror": [
    "https://ne62ahv7.mirror.aliyuncs.com",
    "https://registry.docker-cn.com",
    "https://docker.mirrors.ustc.edu.cn",
    "http://hub-mirror.c.163.com"
  ]
 }
EOF

systemctl daemon-reload && systemctl restart docker

8. 安装k8s

镜像

bash 复制代码

cat > /etc/yum.repos.d/kubernetes.repo << EOF
[kubernetes]
name=Kubernetes
baseurl=http://mirrors.aliyun.com/kubernetes/yum/repos/kubernetes-el7-x86_64
enabled=1
gpgcheck=0
repo_gpgcheck=0
gpgkey=http://mirrors.aliyun.com/kubernetes/yum/doc/yum-key-gpg
	   http://mirrors.aliyun.com/kubernetes/yum/doc/rpm-package-key.gpg
EOF

cat /etc/yum.repos.d/kubernetes.repo

安装

bash 复制代码

yum -y install kubelet-1.23.17 kubeadm-1.23.17 kubectl-1.23.17

systemctl enable kubelet

journalctl -xefu kubelet

9. 异性操作（不同节点之间执行不同命令）

设置hostname

bash 复制代码

# 不同主机上执行
hostnamectl set-hostname master
hostnamectl set-hostname node1
hostnamectl set-hostname node2

执行完之后建议重启
bash 复制代码
reboot

初始化kubernetes

bash 复制代码

# 只在主节点执行
kubeadm init \
--apiserver-advertise-address=172.16.188.175 \
--image-repository=registry.cn-hangzhou.aliyuncs.com/google_containers \
--kubernetes-version=v1.23.17 \
--service-cidr=10.96.0.0/12 \
--pod-network-cidr=10.244.0.0/16 \
--ignore-preflight-errors=all

执行结果不要关掉

$init$ Using Kubernetes version: v1.23.17

$preflight$ Running pre-flight checks

$WARNING SystemVerification$ : this Docker version is not on the list of validated versions: 24.0.7. Latest validated version: 20.10

$preflight$ Pulling images required for setting up a Kubernetes cluster

$preflight$ This might take a minute or two, depending on the speed of your internet connection

$preflight$ You can also perform this action in beforehand using 'kubeadm config images pull'

$certs$ Using certificateDir folder "/etc/kubernetes/pki"

$certs$ Generating "ca" certificate and key

$certs$ Generating "apiserver" certificate and key
$certs\] apiserver serving cert is signed for DNS names \[kubernetes kubernetes.default kubernetes.default.svc kubernetes.default.svc.cluster.local master\] and IPs \[10.96.0.1 172.16.188.175$
$certs$ Generating "apiserver-kubelet-client" certificate and key

$certs$ Generating "front-proxy-ca" certificate and key

$certs$ Generating "front-proxy-client" certificate and key

$certs$ Generating "etcd/ca" certificate and key

$certs$ Generating "etcd/server" certificate and key
$certs\] etcd/server serving cert is signed for DNS names \[localhost master\] and IPs \[172.16.188.175 127.0.0.1 ::1$
$certs$ Generating "etcd/peer" certificate and key
$certs\] etcd/peer serving cert is signed for DNS names \[localhost master\] and IPs \[172.16.188.175 127.0.0.1 ::1$
$certs$ Generating "etcd/healthcheck-client" certificate and key

$certs$ Generating "apiserver-etcd-client" certificate and key

$certs$ Generating "sa" key and public key

$kubeconfig$ Using kubeconfig folder "/etc/kubernetes"

$kubeconfig$ Writing "admin.conf" kubeconfig file

$kubeconfig$ Writing "kubelet.conf" kubeconfig file

$kubeconfig$ Writing "controller-manager.conf" kubeconfig file

$kubeconfig$ Writing "scheduler.conf" kubeconfig file

$kubelet-start$ Writing kubelet environment file with flags to file "/var/lib/kubelet/kubeadm-flags.env"

$kubelet-start$ Writing kubelet configuration to file "/var/lib/kubelet/config.yaml"

$kubelet-start$ Starting the kubelet

$control-plane$ Using manifest folder "/etc/kubernetes/manifests"

$control-plane$ Creating static Pod manifest for "kube-apiserver"

$control-plane$ Creating static Pod manifest for "kube-controller-manager"

$control-plane$ Creating static Pod manifest for "kube-scheduler"

$etcd$ Creating static Pod manifest for local etcd in "/etc/kubernetes/manifests"

$wait-control-plane$ Waiting for the kubelet to boot up the control plane as static Pods from directory "/etc/kubernetes/manifests". This can take up to 4m0s

$apiclient$ All control plane components are healthy after 5.504881 seconds

$upload-config$ Storing the configuration used in ConfigMap "kubeadm-config" in the "kube-system" Namespace

$kubelet$ Creating a ConfigMap "kubelet-config-1.23" in namespace kube-system with the configuration for the kubelets in the cluster

NOTE: The "kubelet-config-1.23" naming of the kubelet ConfigMap is deprecated. Once the UnversionedKubeletConfigMap feature gate graduates to Beta the default name will become just "kubelet-config". Kubeadm upgrade will handle this transition transparently.

$upload-certs$ Skipping phase. Please see --upload-certs
$mark-control-plane\] Marking the node master as control-plane by adding the labels: \[node-role.kubernetes.io/master(deprecated) node-role.kubernetes.io/control-plane node.kubernetes.io/exclude-from-external-load-balancers$ $mark-control-plane\] Marking the node master as control-plane by adding the taints \[node-role.kubernetes.io/master:NoSchedule$
$bootstrap-token$ Using token: bh0p19.4bdguik2fp3y81mv

$bootstrap-token$ Configuring bootstrap tokens, cluster-info ConfigMap, RBAC Roles

$bootstrap-token$ configured RBAC rules to allow Node Bootstrap tokens to get nodes

$bootstrap-token$ configured RBAC rules to allow Node Bootstrap tokens to post CSRs in order for nodes to get long term certificate credentials

$bootstrap-token$ configured RBAC rules to allow the csrapprover controller automatically approve CSRs from a Node Bootstrap Token

$bootstrap-token$ configured RBAC rules to allow certificate rotation for all node client certificates in the cluster

$bootstrap-token$ Creating the "cluster-info" ConfigMap in the "kube-public" namespace

$kubelet-finalize$ Updating "/etc/kubernetes/kubelet.conf" to point to a rotatable kubelet client certificate and key

$addons$ Applied essential addon: CoreDNS

$addons$ Applied essential addon: kube-proxy

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

Alternatively, if you are the root user, you can run:

export KUBECONFIG=/etc/kubernetes/admin.conf

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 172.16.188.175:6443 --token bh0p19.4bdguik2fp3y81mv \

--discovery-token-ca-cert-hash sha256:2327aff6edc65a0ccf11d09ffed3890cf560b56ddde13c47a88026c6e525a0c9

环境配置

普通用户

bash 复制代码

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

root用户

bash 复制代码

echo "export KUBECONFIG=/etc/kubernetes/admin.conf" >> /etc/profile
source /etc/profile

10. 配置`flannel`

只限master节点

flannel （［'ˈflænl]）和calico（［'kælɪkoʊ］）都是用于k8s节点之间容器网络通信的一个k8s组件，flanne可以为不同node节点的分配不同的子网，实现容器间的跨机通信，从而实现整个kubenets层级通信。

下载

bash 复制代码

cd /opt
wget https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml

上传

bash 复制代码

kubectl apply -f /opt/kube-flannel.yml

其他节点

设置hostname

bash 复制代码

# 前面执行过，可以跳过
hostnamectl set-hostname node1

执行kubeadm join命令，该命令是master节点初始化k8s时生成的

bash 复制代码

kubeadm join 172.16.188.175:6443 --token bh0p19.4bdguik2fp3y81mv \
--discovery-token-ca-cert-hash sha256:2327aff6edc65a0ccf11d09ffed3890cf560b56ddde13c47a88026c6e525a0c9

上面命令中token默认有效期为24小时，过期后可以在master节点执行kubeadm token create --print-join-command重新创建token

环境配置

bash 复制代码

echo "export KUBECONFIG=/etc/kubernetes/kubelet.conf" >> /etc/profile
source /etc/profile

验证

bash 复制代码

kubectl get no

以上内容总结自：如何在Centos7中安装Kubernetes_哔哩哔哩_bilibili

关联可参考信息

K8s集群搭建教程-CSDN博客

Kubernetes（K8S）集群部署搭建图文教程（最全）_k8s部署-CSDN博客

部署k8s集群（k8s集群搭建详细实践版）_运维_在路上的阿帅-CSDN学习社区