K8S集群详细搭建步骤
k8s
CentOS
Name | IP | OS |
---|---|---|
k8s-master | 192.168.0.106 | CentOS |
k8s-node1 | 192.168.0.107 | CentOS |
k8s-node2 | 192.168.0.108 | CentOS |
为了方便多次配置,建议执行的命令均封装成脚本
节点
- master 和 node 里均需执行
0.更改主机信息 hostname(/etc/hosts)
# 主节点为k8s-master
# 从节点1为k8s-node1
# 从节点2为k8s-node2
hostnamectl set-hostname k8s-master
su # 立即生效
# 在文件/etc/hosts中添加如下,注意ip地址
192.168.0.106 kmaster.example.com k8s-master
192.168.0.107 kmaster.example.com k8s-node1
192.168.0.108 kmaster.example.com k8s-node2
1.关闭各种东西 ./1_init.sh
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在执行上脚本前,先打开/etc/sysctl.d/kubernetes.conf,添加如下内容:
net.bridge.bridge-nf-call-ip6tables = 1
net.bridge.bridge-nf-call-iptables = 1并安装ntpdate:
yum install -y ntpdate
# ./1_init.sh
systemctl disable firewalld
systemctl stop firewalld
setenforce 0
sed -i --follow-symlinks 's/^SELINUX=enforcing/SELINUX=disabled/' /etc/sysconfig/selinux
sed -i '/swap/d' /etc/fstab
swapoff -a
ntpdate time.windows.com
sysctl --system
2.更新源 ./2_update_yum.sh
更新源之前应当设置 kubernetes 源 ./setrepo.sh
设置kubernetes源之前 /etc/yum.repos.d 下应当没有 kubernetes.repo
# ./setrepo.sh
cat >>/etc/yum.repos.d/kubernetes.repo<<EOF
[kubernetes]
name=Kubernetes baseurl=https://mirrors.aliyun.com/kubernetes/yum/repos/kubernetes-el7-x86_64/ enabled=1
gpgcheck=1
repo_gpgcheck=1 gpgkey=https://mirrors.aliyun.com/kubernetes/yum/doc/yum-key.gpg
https://mirrors.aliyun.com/kubernetes/yum/doc/rpm-package-key.gpg
EOF
# ./2_update_yum.sh
yum clean all
yum makecache
3.安装kubeadm kubelet kubectl ./3_install_kub
# ./3_installkub.sh
yum install -y kubeadm kubelet kubectl
# 现在还不能 start kubelet,要 kubeadm init 之后才能 start
systemctl enable kubelet
4.启动docker ./5_start_docker.sh
启动docker前应该做好的工作
1 安装docker的依赖 install_depofdocker.sh
2 配置稳定的数据源 set_stable_repo.sh
3 安装docker install_docker.sh
4 编辑添加
vim /etc/docker/daemon.json
{
"exec-opts":["native.cgroupdriver=systemd"]}
# install_depofdocker.sh
sudo yum install -y yum-utils device-mapper-persistent-data lvm2
# set_stable_repo.sh
yum-config-manager --add-repo http://mirrors.aliyun.com/docker-ce/linux/cento s/docker-ce.repo
# install_docker.sh
yum install docker-ce docker-ce-cli containerd.io -y
# 5_start_docker.sh
systemctl enable docker
systemctl start docker
systemctl status docker
master
- 只有 master 节点操作如下步骤
5.初始化kubeadm ./6_kuinit.sh
# ./6_kuinit.sh
# 修改为master的ip
kubeadm init --apiserver-advertise-address=192.168.0.106 --pod-network-cidr=10.244.0.0/16 --image-repository registry.aliyuncs.com/google_containers --kubernetes-version=v1.18.2
出现报错
Cannot connect to the Docker daemon at tcp://localhost:2375. Is the docker daemon running?
解决过程:
# 配置DOCKER_HOST
sudo vim /etc/profile.d/docker.sh
# 添加下面内容:
export DOCKER_HOST=tcp://localhost:2375
# 应用
source /etc/profile
source /etc/bashrc
# 配置启动文件
sudo vim /lib/systemd/system/docker.service
# 修改语句 ExecStart=/usr/bin/dockerd -H unix://
# 为如下语句:
ExecStart=/usr/bin/dockerd -H tcp://0.0.0.0:2375 -H unix:///var/run/docker.sock -H tcp://0.0.0.0:7654
# 重载配置和重启
sudo systemctl daemon-reload
sudo systemctl restart docker.service
# 查看
docker version
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解决上述报错之后重新执行./6_kuinit.sh,等待一段时间出现successfully的提示就初始化成功!
记录如下输入,为master节点后续操作。
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记录下最后一段,为node节点加入集群的命令。
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6.启动kubelet ./4_startKubelet.sh
# ./4_startKubelet.sh
systemctl enable kubelet
systemctl start kubelet
systemctl status kubelet
7.执行初始化的后续操作脚本 ./7_after_kubeadm.sh
# ./7_after_kubeadm.sh
# 第五步输出中提示的命令
mkdir -p $HOME/.kube
sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
sudo chown $(id -u):$(id -g) $HOME/.kube/config
查看master节点情况可用命令
kubectl get nodes
docker images
kubectl get pod -n kube-system
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8.在 master 节点上安装 calico 网络 ./8_calico.sh
使用 kubectl get pod -n kube-system 查看服务器进程状态
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9.集群添加主节点 ./9_add_cluster.sh
# ./9_add_cluster.sh
kubeadm token create --print-join-command
记下最后两行,这是从节点加入集群的命令
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node
- 只有 node 节点操作如下步骤
将主节点加入集群后,提示的,从节点加入集群命令封装成脚本./node_join.sh
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在从节点运行脚本,加入集群
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发现加入结点失败。
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原因是token过期,在主节点重新生成token。
kubeadm token create --print-join-command
在master查看节点状态,发现从节点是NotReady
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用命令启动kubelet
systemctl enable kubelet
systemctl start kubelet
需要等待一段时间,主节点查看节点状态才是Ready