kubeadm初始化集群
1. 环境准备
1.1 准备4台机器，安装CentOS7.9(节点名跟ip均已设置完成)，并且ssh已经互通。
10.0.0.69 master1 10.0.0.71 node3 10.0.0.72 node4 10.0.0.73 node5
1.2 系统初始化
以下操作没有特殊说明默认在每台服务器上都执行命令
关闭防火墙
systemctl stop firewalld
systemctl disable firewalld
关闭 selinux
sed -i 's/enforcing/disabled/' /etc/selinux/config setenforce 0
关闭 swap
swapoff -a sed -ri 's/.*swap.*/#&/' /etc/fstab
在 master节点 添加 其它两个节点hosts
cat >> /etc/hosts << EOF 10.0.0.69 master1 node1 10.0.0.70 master2 node2 10.0.0.71 node3 10.0.0.72 node4 10.0.0.73 node5 EOF
设置网络
cat > /etc/sysctl.d/k8s.conf << EOF net.bridge.bridge-nf-call-ip6tables = 1 net.bridge.bridge-nf-call-iptables = 1 EOF
让配置生效
sysctl --system
同步服务器时间
yum install ntpdate -y ntpdate time.windows.com
1.3安装依赖环境
每台服务器安装Docker
wget https://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo -O /etc/yum.repos.d/docker-ce.repo yum -y install docker-ce systemctl enable docker && systemctl start docker
修改docker源
docker的cgroup驱动程序默认设置为system。默认情况下Kubernetes cgroup为systemd，我们需要更改Docker cgroup驱动
cat > /etc/docker/daemon.json << EOF { "registry-mirrors": ["https://b9pmyelo.mirror.aliyuncs.com"], "exec-opts": ["native.cgroupdriver=systemd"] } EOF
systemctl daemon-reload
systemctl restart docker
修改k8s的阿里yum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
安装kubeadm，kubelet和kubectl
yum install -y kubelet-1.23.0 kubeadm-1.23.0 kubectl-1.23.0 systemctl enable kubelet
2.部署k8s节点
在master节点启动相关组件 注意把对应ip改成你的master节点的ip（10.0.0.69）
kubeadm init --apiserver-advertise-address=10.0.0.69 --image-repository registry.aliyuncs.com/google_containers --kubernetes-version v1.23.0 --service-cidr=10.96.0.0/12 --pod-network-cidr=10.244.0.0/16
执行完毕查看结果 会看到successfully！下边有一段脚本
Your Kubernetes control-plane has initialized successfully!
To start using your cluster, you need to run the following as a regular user: mkdir -pHOME/.kube sudo cp -i /etc/kubernetes/admin.confHOM**E/.kubesudoc**p?i/etc/kubernete**s/admin.con**fHOME/.kube/config sudo chown(id -u)??i**d?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 10.0.0.69:6443 --token hpk828.gxd7cpwtmmt9mgxy \
--discovery-token-ca-cert-hash sha256:061ed4ef4f6d1f42d8052e86bc3b41dfdfff4d7e1e7c6d933c6e40ebeacb2
以下操作基于上边安装成功的信息来操作(执行的时候为你安装成功的脚本信息)
我们复制上边的脚本在master节点执行
mkdir -p $HOME/.kube sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config sudo chown $(id -u):$(id -g) $HOME/.kube/config
然后看上边最后一段脚本 在node节点 使用kubeadm join命令把node加入到master节点
kubeadm join 10.0.0.69:6443 --token hpk828.gxd7cpwtmmt9mgxy \ --discovery-token-ca-cert-hash sha256:061ed4ef4f6d1f42d8052e86bc3b41dfdfff4d7e1e7c6d933c6e40ebeacb2
注意 默认token有效期为24小时，当过期之后，该token就不可用了。这时就需要重新创建token，操作如下：
kubeadm token create --print-join-command
部署CNI网络插件
下载flannel.yml(https://raw.githubusercontent.com/flannel-io/flannel/master/Documentation/kube-flannel.yml)
---
apiVersion: policy/v1beta1
kind: PodSecurityPolicy
metadata:
name: psp.flannel.unprivileged
annotations:
seccomp.security.alpha.kubernetes.io/allowedProfileNames: docker/default
seccomp.security.alpha.kubernetes.io/defaultProfileName: docker/default
apparmor.security.beta.kubernetes.io/allowedProfileNames: runtime/default
apparmor.security.beta.kubernetes.io/defaultProfileName: runtime/default
spec:
privileged: false
volumes:
- configMap
- secret
- emptyDir
- hostPath
allowedHostPaths:
- pathPrefix: "/etc/cni/net.d"
- pathPrefix: "/etc/kube-flannel"
- pathPrefix: "/run/flannel"
readOnlyRootFilesystem: false
# Users and groups
runAsUser:
rule: RunAsAny
supplementalGroups:
rule: RunAsAny
fsGroup:
rule: RunAsAny
# Privilege Escalation
allowPrivilegeEscalation: false
defaultAllowPrivilegeEscalation: false
# Capabilities
allowedCapabilities: ['NET_ADMIN', 'NET_RAW']
defaultAddCapabilities: []
requiredDropCapabilities: []
# Host namespaces
hostPID: false
hostIPC: false
hostNetwork: true
hostPorts:
- min: 0
max: 65535
# SELinux
seLinux:
# SELinux is unused in CaaSP
rule: 'RunAsAny'
---
kind: ClusterRole
apiVersion: rbac.authorization.k8s.io/v1
metadata:
name: flannel
rules:
- apiGroups: ['extensions']
resources: ['podsecuritypolicies']
verbs: ['use']
resourceNames: ['psp.flannel.unprivileged']
- apiGroups:
- ""
resources:
- pods
verbs:
- get
- apiGroups:
- ""
resources:
- nodes
verbs:
- list
- watch
- apiGroups:
- ""
resources:
- nodes/status
verbs:
- patch
---
kind: ClusterRoleBinding
apiVersion: rbac.authorization.k8s.io/v1
metadata:
name: flannel
roleRef:
apiGroup: rbac.authorization.k8s.io
kind: ClusterRole
name: flannel
subjects:
- kind: ServiceAccount
name: flannel
namespace: kube-system
---
apiVersion: v1
kind: ServiceAccount
metadata:
name: flannel
namespace: kube-system
---
kind: ConfigMap
apiVersion: v1
metadata:
name: kube-flannel-cfg
namespace: kube-system
labels:
tier: node
app: flannel
data:
cni-conf.json: |
{
"name": "cbr0",
"cniVersion": "0.3.1",
"plugins": [
{
"type": "flannel",
"delegate": {
"hairpinMode": true,
"isDefaultGateway": true
}
},
{
"type": "portmap",
"capabilities": {
"portMappings": true
}
}
]
}
net-conf.json: |
{
"Network": "10.244.0.0/16",
"Backend": {
"Type": "vxlan"
}
}
---
apiVersion: apps/v1
kind: DaemonSet
metadata:
name: kube-flannel-ds
namespace: kube-system
labels:
tier: node
app: flannel
spec:
selector:
matchLabels:
app: flannel
template:
metadata:
labels:
tier: node
app: flannel
spec:
affinity:
nodeAffinity:
requiredDuringSchedulingIgnoredDuringExecution:
nodeSelectorTerms:
- matchExpressions:
- key: kubernetes.io/os
operator: In
values:
- linux
hostNetwork: true
priorityClassName: system-node-critical
tolerations:
- operator: Exists
effect: NoSchedule
serviceAccountName: flannel
initContainers:
- name: install-cni-plugin
#image: flannelcni/flannel-cni-plugin:v1.0.1 for ppc64le and mips64le (dockerhub limitations may apply)
image: rancher/mirrored-flannelcni-flannel-cni-plugin:v1.0.1
command:
- cp
args:
- -f
- /flannel
- /opt/cni/bin/flannel
volumeMounts:
- name: cni-plugin
mountPath: /opt/cni/bin
- name: install-cni
#image: flannelcni/flannel:v0.17.0 for ppc64le and mips64le (dockerhub limitations may apply)
image: rancher/mirrored-flannelcni-flannel:v0.17.0
command:
- cp
args:
- -f
- /etc/kube-flannel/cni-conf.json
- /etc/cni/net.d/10-flannel.conflist
volumeMounts:
- name: cni
mountPath: /etc/cni/net.d
- name: flannel-cfg
mountPath: /etc/kube-flannel/
containers:
- name: kube-flannel
#image: flannelcni/flannel:v0.17.0 for ppc64le and mips64le (dockerhub limitations may apply)
image: rancher/mirrored-flannelcni-flannel:v0.17.0
command:
- /opt/bin/flanneld
args:
- --ip-masq
- --kube-subnet-mgr
resources:
requests:
cpu: "100m"
memory: "50Mi"
limits:
cpu: "100m"
memory: "50Mi"
securityContext:
privileged: false
capabilities:
add: ["NET_ADMIN", "NET_RAW"]
env:
- name: POD_NAME
valueFrom:
fieldRef:
fieldPath: metadata.name
- name: POD_NAMESPACE
valueFrom:
fieldRef:
fieldPath: metadata.namespace
volumeMounts:
- name: run
mountPath: /run/flannel
- name: flannel-cfg
mountPath: /etc/kube-flannel/
- name: xtables-lock
mountPath: /run/xtables.lock
volumes:
- name: run
hostPath:
path: /run/flannel
- name: cni-plugin
hostPath:
path: /opt/cni/bin
- name: cni
hostPath:
path: /etc/cni/net.d
- name: flannel-cfg
configMap:
name: kube-flannel-cfg
- name: xtables-lock
hostPath:
path: /run/xtables.lock
type: FileOrCreate
#执行命令
kubectl apply -f kube-flannel.yaml
查看集群状态 使用kubectl命令查看节点状态
kubectl get nodes
3.集群测试
使用deployment创建一个nginx应用
kubectl create deployment nginx --image=nginx
使用expose对外暴露访问端口
kubectl expose deployment nginx --port=80 --type=NodePort
查看暴露的端口号
kubectl get pod,svc
可以通过任一节点访问31602，将会显示nginx的欢迎页面
参考https://www.cnblogs.com/vinsent/p/15917739.html