Kubeadm方式部署Kubernetes集群
环境准备
预先安装好3台主机,需要有上网权限,此处为VM,与主机网络模式为NAT
| HostName | OS | IP |
|---|---|---|
| k8s-master | CentOS Linux release 7.9.2009 (Core) | 172.16.252.88 |
| k8s-node1 | CentOS Linux release 7.9.2009 (Core) | 172.16.252.89 |
| k8s-node2 | CentOS Linux release 7.9.2009 (Core) | 172.16.252.90 |
所有节点均需要设置
关闭 主机防火墙
systemctl stop firewalld systemctl disable firewalld关闭SELinux
sed -i 's/enforcing/disabled/' /etc/selinux/config #永久关闭 setenforce 0 #临时关闭关闭swap分区
swapoff -a #临时关闭 sed -ri 's/.*swap.* /#&/' /etc/fstab #永久关闭设置主机名
hostnamectl set-hostname [hostname]在
master节点中添加hostscat >> /etc/hosts <<EOF 172.16.252.88 k8s-master 172.16.252.89 k8s-node1 172.16.252.90 k8s-node2 EOF将桥接的网卡流量传到iptables
cat > /etc/sysctl.d/k8s.conf <<EOF net.bridge.bridge-nf-call-ip6tables = 1 net.bridge.bridge-nf-call-iptables = 1 EOF sysctl --system #生效时间同步
yum -y install ntpdate ntpdate time.windows.com
所有节点安装Docker/Kubeadm/Kublet
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 yum -y install docker-ce-20.10.6-3.el7.x86_64 systemctl enable docker && systemctl start docker #配置镜像加速器 cat > /etc/docker/daemon.json << EOF { "registry-mirrors":[https://kod2rnzj.mirror.aliyuncs.com] } systemctl restart docker添加阿里云YUM源
#可用 cat > /etc/yum.repos.d/kubeadm.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 EOFKubeadm/Kubelet/Kubectl 安装
yum install -y kubelet-1.20.1 kubeadm-1.20.1 kubectl-1.20.1 systemctl enable kubelet
部署Kubernetes Master
#master节点部署
kubeadm init --apiserver-advertise-address=172.16.252.88 --image-repository registry.aliyuncs.com/google_containers --kubernetes-version v1.20.1 --service-cidr=10.96.0.0/12 --pod-network-cidr=10.244.0.0/16
#拉取Kubernetes 核心组件apiserver,contorll,etcd,proxy,pause,coredns,scheduller 镜像
#配置Kubernetes master
mkdir -p $HOME/.kube
cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
chown $(id -u) $HOME/.kube/config
chown $(id -g) $HOME/.kube/config
kubectl get nodes #查看集群节点node节点加入集群
#node节点加入集群
kubeadm join 172.16.252.88:6443 --token xxx.xxxxxxxxxxx \ #随机生成token
--discovery-token-ca-cert-hash sha256 xxxxxxxxxxxxxxx
#默认token有效期为24小时,过期后需重新创建token
kubeadm token create --print-join-command部署CNI网络插件
#github地址
wget https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml
#应用flannel生成
kubectl apply -f kube-flannel.yml
#检查kube-system系统命名空间内组件
kubectl get pods -n kube-system# kube-flannel.yml 内容
---
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
image: quay.io/coreos/flannel:v0.14.0-rc1
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: quay.io/coreos/flannel:v0.14.0-rc1
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/
volumes:
- name: run
hostPath:
path: /run/flannel
- name: cni
hostPath:
path: /etc/cni/net.d
- name: flannel-cfg
configMap:
name: kube-flannel-cfg测试K8s集群
#查看集群状态
kubectl get nodes
NAME STATUS ROLES AGE VERSION
k8s-master Ready control-plane,master 48m v1.20.1
k8s-node1 Ready <none> 39m v1.20.1
k8s-node2 Ready <none> 37m v1.20.1#查看集群内容器分布状态以及集群内服务状态
kubectl get pods,svc -n kube-system -o wide
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
pod/coredns-7f89b7bc75-5b47p 1/1 Running 0 50m 10.244.0.3 k8s-master <none> <none>
pod/coredns-7f89b7bc75-ncpds 1/1 Running 0 50m 10.244.0.2 k8s-master <none> <none>
pod/etcd-k8s-master 1/1 Running 0 50m 172.16.252.88 k8s-master <none> <none>
pod/kube-apiserver-k8s-master 1/1 Running 0 50m 172.16.252.88 k8s-master <none> <none>
pod/kube-controller-manager-k8s-master 1/1 Running 0 50m 172.16.252.88 k8s-master <none> <none>
pod/kube-flannel-ds-49pjb 1/1 Running 0 17m 172.16.252.88 k8s-master <none> <none>
pod/kube-flannel-ds-ktpfk 0/1 Init:ImagePullBackOff 0 17m 172.16.252.90 k8s-node2 <none> <none>
pod/kube-flannel-ds-zpvmw 0/1 Init:0/1 0 17m 172.16.252.89 k8s-node1 <none> <none>
pod/kube-proxy-29n6x 1/1 Running 0 50m 172.16.252.88 k8s-master <none> <none>
pod/kube-proxy-nbvqf 1/1 Running 0 42m 172.16.252.89 k8s-node1 <none> <none>
pod/kube-proxy-x7lbt 1/1 Running 0 39m 172.16.252.90 k8s-node2 <none> <none>
pod/kube-scheduler-k8s-master 1/1 Running 0 50m 172.16.252.88 k8s-master <none> <none>
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE SELECTOR
service/kube-dns ClusterIP 10.96.0.10 <none> 53/UDP,53/TCP,9153/TCP 50m k8s-app=kube-dns在Kubernetes集群中创建一个pod,验证是否运行正常
#创建并部署一个pod命名为nginx,使用nginx镜像
kubectl create depoloyment nginx --image=nginx
#暴露nginx端口为80,模式为节点端口,默认内部容器节点为30000~32767
kubectl expose deployment nginx --port=80 --type=NodePort
#查看pod状态以及svc状态
kubectl get pod,svc
#使用http://K8s任意节点ip:port访问
