这里写目录标题
- kubeadm1.25
-
- 一.环境准备
-
- 二.所有节点安装docker
- 三.所有节点安装kubeadm，kubelet和kubectl
-
- 1.定义kubernetes源
- 2.部署K8S集群
- 3.内核参数优化方案
kubeadm1.25
一.环境准备
1.网络分配
master（2C/4G，cpu核心数要求大于2） 192.168.82.100 docker、kubeadm、kubelet、kubectl、flannel
node01（2C/2G） 192.168.82.101 docker、kubeadm、kubelet、kubectl、flannel
node02（2C/2G） 192.168.82.102 docker、kubeadm、kubelet、kubectl、flannel
Harbor节点（hub.kgc.com） 192.168.82.103 docker、docker-compose、harbor-offline-v1.2.2
2.系统设置
//所有节点，关闭防火墙规则，关闭selinux，关闭swap交换
systemctl stop firewalld
systemctl disable firewalld
setenforce 0
sed -i 's/enforcing/disabled/' /etc/selinux/config
iptables -F && iptables -t nat -F && iptables -t mangle -F && iptables -X
swapoff -a
sed -ri 's/.*swap.*/#&/' /etc/fstab
for i in $(ls /usr/lib/modules/$(uname -r)/kernel/net/netfilter/ipvs|grep -o "^[^.]*");do echo $i; /sbin/modinfo -F filename $i >/dev/null 2>&1 && /sbin/modprobe $i;done
//修改主机名
hostnamectl set-hostname master01
hostnamectl set-hostname node01
hostnamectl set-hostname node02
//所有节点修改hosts文件
vim /etc/hosts
192.168.82.100 master01
192.168.82.101 node01
192.168.82.102 node02
//调整内核参数
cat > /etc/sysctl.d/kubernetes.conf << EOF
#开启网桥模式，可将网桥的流量传递给iptables链
net.bridge.bridge-nf-call-ip6tables=1
net.bridge.bridge-nf-call-iptables=1
#关闭ipv6协议
net.ipv6.conf.all.disable_ipv6=1
net.ipv4.ip_forward=1
EOF
//生效参数
sysctl --system
二.所有节点安装docker
yum install -y yum-utils device-mapper-persistent-data lvm2
yum-config-manager --add-repo https://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo
yum install -y docker-ce docker-ce-cli containerd.io
mkdir /etc/docker
cat > /etc/docker/daemon.json <<EOF
{
"registry-mirrors": ["https://xxxxxxx.mirror.aliyuncs.com"],
"exec-opts": ["native.cgroupdriver=systemd"],
"log-driver": "json-file",
"log-opts": {
"max-size": "100m"
}
}
EOF
systemctl daemon-reload
systemctl restart docker.service
systemctl enable docker.service
docker info | grep "Cgroup Driver"
Cgroup Driver: systemd
//所有主机安装 cri-dockerd
Kubernetes自v1.24移除了对docker-shim的支持，而Docker Engine默认又不支持CRI规范，因而二者将无法直接完成整合。 为此，Mirantis和Docker联合创建了cri-dockerd项目，用于为Docker Engine提供一个能够支持到CRI规范的垫片，从而能够让Kubernetes基于CRI控制Docker 。
项目地址：https://github.com/Mirantis/cri-dockerd
cd /opt/
wget https://github.com/Mirantis/cri-dockerd/releases/download/v0.2.6/cri-dockerd-0.2.6-3.el7.x86_64.rpm
yum localinstall -y cri-dockerd-0.2.6-3.el7.x86_64.rpm
vim /lib/systemd/system/cri-docker.service
ExecStart=/usr/bin/cri-dockerd --network-plugin=cni --pod-infra-container-image=registry.aliyuncs.com/google_containers/pause:3.8
systemctl daemon-reload
systemctl enable --now cri-docker
三.所有节点安装kubeadm，kubelet和kubectl
1.定义kubernetes源
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=0
repo_gpgcheck=0
gpgkey=https://mirrors.aliyun.com/kubernetes/yum/doc/yum-key.gpg https://mirrors.aliyun.com/kubernetes/yum/doc/rpm-package-key.gpg
EOF
yum install -y kubelet-1.25.4 kubeadm-1.25.4 kubectl-1.25.4
kubeadm version
//开机自启kubelet
systemctl enable kubelet.service
2.部署K8S集群
//在 master01 节点上设置集群初始化配置文件
kubeadm config print init-defaults > /opt/kubeadm-config.yaml
cd /opt/
vim kubeadm-config.yaml
apiVersion: kubeadm.k8s.io/v1beta3
bootstrapTokens:
- groups:
- system:bootstrappers:kubeadm:default-node-token
token: abcdef.0123456789abcdef
ttl: 24h0m0s
usages:
- signing
- authentication
kind: InitConfiguration
localAPIEndpoint:
advertiseAddress: 192.168.82.100
bindPort: 6443
nodeRegistration:
criSocket: unix:///var/run/cri-dockerd.sock
imagePullPolicy: IfNotPresent
name: master01
taints:
- effect: NoSchedule
key: node-role.kubernetes.io/master
---
apiServer:
timeoutForControlPlane: 4m0s
apiVersion: kubeadm.k8s.io/v1beta3
certificatesDir: /etc/kubernetes/pki
clusterName: kubernetes
controllerManager: {}
dns: {}
etcd:
local:
dataDir: /var/lib/etcd
imageRepository: registry.aliyuncs.com/google_containers
kind: ClusterConfiguration
kubernetesVersion: v1.25.4
networking:
dnsDomain: cluster.local
podSubnet: 10.244.0.0/16
serviceSubnet: 10.96.0.0/16
scheduler: {}
---
apiVersion: kubeproxy.config.k8s.io/v1alpha1
kind: KubeProxyConfiguration
mode: ipvs
//查看初始化需要的镜像
kubeadm config images list --kubernetes-version 1.25.4
//所有节点拉取镜像
for i in node01 node02; do scp /opt/kubeadm-config.yaml $i:/opt/; done
kubeadm config images pull --config /opt/kubeadm-config.yaml
//master01 节点初始化kubeadm
方法一：
kubeadm init --config=kubeadm-config.yaml --upload-certs | tee kubeadm-init.log
//查看 kubeadm-init 日志
less kubeadm-init.log
//kubernetes配置文件目录
ls /etc/kubernetes/
//存放ca等证书和密码的目录
ls /etc/kubernetes/pki
方法二：
kubeadm init \
--apiserver-advertise-address=192.168.80.10 \
--image-repository registry.aliyuncs.com/google_containers \
--kubernetes-version v1.25.4 \
--service-cidr=10.96.0.0/16 \
--pod-network-cidr=10.244.0.0/16 \
--cri-socket /var/run/cri-dockerd.sock \
--upload-certs
--------------------------------------------------------------------------------------------
初始化集群需使用kubeadm init命令，可以指定具体参数初始化，也可以指定配置文件初始化。
可选参数：
--apiserver-advertise-address：apiserver通告给其他组件的IP地址，一般应该为Master节点的用于集群内部通信的IP地址，0.0.0.0表示节点上所有可用地址
--apiserver-bind-port：apiserver的监听端口，默认是6443
--cert-dir：通讯的ssl证书文件，默认/etc/kubernetes/pki
--control-plane-endpoint：多主节点必选项，用于指定控制平面的固定访问地址。注意:kubeadm不支持将没有--control-plane-endpoint参数的单个控制平面集群转换为高可用性集群
--image-repository：拉取镜像的镜像仓库，默认是k8s.gcr.io
--kubernetes-version：指定kubernetes版本
--pod-network-cidr：pod资源的网段，需与pod网络插件的值设置一致。Flannel网络插件的默认为10.244.0.0/16，Calico插件的默认值为192.168.0.0/16；
--service-cidr：service资源的网段
--service-dns-domain：service全域名的后缀，默认是cluster.local
--token-ttl：默认token的有效期为24小时，0表示永不过期
--cri-socket
---------------------------------------------------------------------------------------------
方法二初始化后需要修改 kube-proxy 的 configmap，开启 ipvs
kubectl edit cm kube-proxy -n=kube-system
修改mode: ipvs
提示：
......
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) $HOME/.kube/config
You should now deploy a pod network to the cluster.
Run "kubectl apply -f [podnetwork].yaml" with one of the options listed at:
https://kubernetes.io/docs/concepts/cluster-administration/addons/
Then you can join any number of worker nodes by running the following on each as root:
kubeadm join 192.168.82.100:6443 --token rc0kfs.a1sfe3gl4dvopck5 \
--discovery-token-ca-cert-hash sha256:864fe553c812df2af262b406b707db68b0fd450dc08b34efb73dd5a4771d37a2
//设定kubectl
kubectl需经由API server认证及授权后方能执行相应的管理操作，kubeadm 部署的集群为其生成了一个具有管理员权限的认证配置文件 /etc/kubernetes/admin.conf，它可由 kubectl 通过默认的 “$HOME/.kube/config” 的路径进行加载。
mkdir -p $HOME/.kube
cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
chown $(id -u):$(id -g) $HOME/.kube/config
//所有节点部署网络插件flannel
mv /opt/cni /opt/cni_bak
mkdir -p /opt/cni/bin
tar zxvf cni-plugins-linux-amd64-v1.1.1.tgz -C /opt/cni/bin
方法一：
cd /opt
docker load < flannel.tar
docker load < flannel-cni-plugin.tar
kubectl apply -f kube-flannel.yml
方法二：
kubectl apply -f https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml
//在 node 节点上执行 kubeadm join 命令加入群集
kubeadm join 192.168.82.100:6443 --token rc0kfs.a1sfe3gl4dvopck5 \
--discovery-token-ca-cert-hash sha256:864fe553c812df2af262b406b707db68b0fd450dc08b34efb73dd5a4771d37a2 \
--cri-socket /var/run/cri-dockerd.sock
//在master节点查看节点状态
kubectl get nodes
NAME STATUS ROLES AGE VERSION
master01 Ready control-plane 88m v1.25.4
node01 Ready <none> 110s v1.25.4
node02 Ready <none> 105s v1.25.4
kubectl get pods -A
NAMESPACE NAME READY STATUS RESTARTS AGE
kube-flannel kube-flannel-ds-lc7lg 1/1 Running 0 83m
kube-flannel kube-flannel-ds-phlnb 1/1 Running 0 88s
kube-flannel kube-flannel-ds-wlvvk 1/1 Running 0 93s
kube-system coredns-c676cc86f-5x7b5 1/1 Running 0 88m
kube-system coredns-c676cc86f-8wxg7 1/1 Running 0 88m
kube-system etcd-master01 1/1 Running 0 88m
kube-system kube-apiserver-master01 1/1 Running 0 88m
kube-system kube-controller-manager-master01 1/1 Running 0 88m
kube-system kube-proxy-rjs6g 1/1 Running 0 88s
kube-system kube-proxy-vp2b5 1/1 Running 0 88m
kube-system kube-proxy-xnllf 1/1 Running 0 93s
kube-system kube-scheduler-master01 1/1 Running 0 88m
//测试 pod 资源创建
kubectl create deployment nginx --image=nginx
kubectl get pods -o wide
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
nginx-554b9c67f9-zr2xs 1/1 Running 0 14m 10.244.1.2 node01 <none> <none>
//暴露端口提供服务
kubectl expose deployment nginx --port=80 --type=NodePort
kubectl get svc
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 25h
nginx NodePort 10.96.15.132 <none> 80:32698/TCP 4s
//测试访问
curl http://node01:32698
//扩展3个副本
kubectl scale deployment nginx --replicas=3
kubectl get pods -o wide
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
nginx-554b9c67f9-9kh4s 1/1 Running 0 66s 10.244.1.3 node01 <none> <none>
nginx-554b9c67f9-rv77q 1/1 Running 0 66s 10.244.2.2 node02 <none> <none>
nginx-554b9c67f9-zr2xs 1/1 Running 0 17m 10.244.1.2 node01 <none> <none>
//部署 Dashboard
kubectl apply -f https://raw.githubusercontent.com/kubernetes/dashboard/v2.6.1/aio/deploy/recommended.yaml
3.内核参数优化方案
cat > /etc/sysctl.d/kubernetes.conf <<EOF
net.bridge.bridge-nf-call-iptables=1
net.bridge.bridge-nf-call-ip6tables=1
net.ipv4.ip_forward=1
net.ipv4.tcp_tw_recycle=0
vm.swappiness=0 #禁止使用 swap 空间，只有当系统内存不足（OOM）时才允许使用它
vm.overcommit_memory=1 #不检查物理内存是否够用
vm.panic_on_oom=0 #开启 OOM
fs.inotify.max_user_instances=8192
fs.inotify.max_user_watches=1048576
fs.file-max=52706963 #指定最大文件句柄数
fs.nr_open=52706963 #仅4.4以上版本支持
net.ipv6.conf.all.disable_ipv6=1
net.netfilter.nf_conntrack_max=2310720
EOF
初始化失败，进行的操作
