K8S快速部署

- 前置虚拟机环境
- 正式部署
- BUG解决

前置虚拟机环境

每个虚拟机配置一次就好

#关闭防火墙
systemctl stop firewalld
systemctl disable firewalld
#关闭 selinux
sed -i 's/enforcing/disabled/' /etc/selinux/config # 永久
setenforce 0 # 临时
#关闭 swap
swapoff -a # 临时
vim /etc/fstab # 永久
#将桥接的 IPv4 流量传递到 iptables 的链
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 install ntpdate -y
ntpdate time.windows.com

#主机名
hostnamectl set-hostname <hostname>

#在 master 添加 hosts：
cat >> /etc/hosts << EOF
192.168.235.139 k8s-master
192.168.235.133 k8s-node1
192.168.235.134 k8s-node2
EOF

没有Docker需要先安装并更换镜像源

添加 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 kubeadm kubectl
systemctl enable kubelet

正式部署

在 192.168.235.139（Master）执行

kubeadm init \
--apiserver-advertise-address=192.168.235.139 \
--image-repository registry.aliyuncs.com/google_containers \
--kubernetes-version v1.18.0 \
--service-cidr=10.96.0.0/12 \
--pod-network-cidr=10.244.0.0/16

这条指令执行完后会自动部署k8s的容器，执行完成后会有

kubeadm join 192.168.235.139:6443 --token 5l9p1e.xzn5a7jv3j75l9v0     --discovery-token-ca-cert-hash sha256:41a451baae921a44253243fc54ce7efb604db7df42fb541802337d08868a4a73

此时在从节点输入上述指令，即可加入集群

kubectl get nodes #测试

执行完后正常应该是都ready了，然后docker ps集群的各个节点也会多出很多k8s相关容器
在这里插入图片描述

使用 kubectl 工具

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

这个我没加后面也能跑。。。

安装 Pod 网络插件（CNI）

kubectl apply –f https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kubeflannel.yml

确保能够访问到 quay.io 这个 registery。如果 Pod 镜像下载失败，可以改这个镜像地址
这个不一定能连上，首先要试试

ping baidu.com

看能不能ping通外网
不行的话需要在DNS加个114.114.114.114
具体参考解决：ping: www.baidu.com: 未知的名称或服务

能ping通外网以后可以把raw.githubusercontent.com换成镜像源或者添加对应的ip，这个网上有相应教程，搜这个网址的关键词就行

或者直接自己创建

cat <<EOF > kube-flannel.yml
---
apiVersion: policy/v1beta1
kind: PodSecurityPolicy
metadata:name: psp.flannel.unprivilegedannotations:seccomp.security.alpha.kubernetes.io/allowedProfileNames: docker/defaultseccomp.security.alpha.kubernetes.io/defaultProfileName: docker/defaultapparmor.security.beta.kubernetes.io/allowedProfileNames: runtime/defaultapparmor.security.beta.kubernetes.io/defaultProfileName: runtime/default
spec:privileged: falsevolumes:- configMap- secret- emptyDir- hostPathallowedHostPaths:- pathPrefix: "/etc/cni/net.d"- pathPrefix: "/etc/kube-flannel"- pathPrefix: "/run/flannel"readOnlyRootFilesystem: false# Users and groupsrunAsUser:rule: RunAsAnysupplementalGroups:rule: RunAsAnyfsGroup:rule: RunAsAny# Privilege EscalationallowPrivilegeEscalation: falsedefaultAllowPrivilegeEscalation: false# CapabilitiesallowedCapabilities: ['NET_ADMIN', 'NET_RAW']defaultAddCapabilities: []requiredDropCapabilities: []# Host namespaceshostPID: falsehostIPC: falsehostNetwork: truehostPorts:- min: 0max: 65535# SELinuxseLinux:# SELinux is unused in CaaSPrule: '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:- podsverbs:- get
- apiGroups:- ""resources:- nodesverbs:- list- watch
- apiGroups:- ""resources:- nodes/statusverbs:- patch
---
kind: ClusterRoleBinding
apiVersion: rbac.authorization.k8s.io/v1
metadata:name: flannel
roleRef:apiGroup: rbac.authorization.k8s.iokind: ClusterRolename: flannel
subjects:
- kind: ServiceAccountname: flannelnamespace: kube-system
---
apiVersion: v1
kind: ServiceAccount
metadata:name: flannelnamespace: kube-system
---
kind: ConfigMap
apiVersion: v1
metadata:name: kube-flannel-cfgnamespace: kube-systemlabels:tier: nodeapp: 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-dsnamespace: kube-systemlabels:tier: nodeapp: flannel
spec:selector:matchLabels:app: flanneltemplate:metadata:labels:tier: nodeapp: flannelspec:affinity:nodeAffinity:requiredDuringSchedulingIgnoredDuringExecution:nodeSelectorTerms:- matchExpressions:- key: kubernetes.io/osoperator: Invalues:- linuxhostNetwork: truepriorityClassName: system-node-criticaltolerations:- operator: Existseffect: NoScheduleserviceAccountName: flannelinitContainers:- name: install-cni-pluginimage: rancher/mirrored-flannelcni-flannel-cni-plugin:v1.0.0command:- cpargs:- -f- /flannel- /opt/cni/bin/flannelvolumeMounts:- name: cni-pluginmountPath: /opt/cni/bin- name: install-cniimage: quay.io/coreos/flannel:v0.15.1command:- cpargs:- -f- /etc/kube-flannel/cni-conf.json- /etc/cni/net.d/10-flannel.conflistvolumeMounts:- name: cnimountPath: /etc/cni/net.d- name: flannel-cfgmountPath: /etc/kube-flannel/containers:- name: kube-flannelimage: quay.io/coreos/flannel:v0.15.1command:- /opt/bin/flanneldargs:- --ip-masq- --kube-subnet-mgrresources:requests:cpu: "100m"memory: "50Mi"limits:cpu: "100m"memory: "50Mi"securityContext:privileged: falsecapabilities:add: ["NET_ADMIN", "NET_RAW"]env:- name: POD_NAMEvalueFrom:fieldRef:fieldPath: metadata.name- name: POD_NAMESPACEvalueFrom:fieldRef:fieldPath: metadata.namespacevolumeMounts:- name: runmountPath: /run/flannel- name: flannel-cfgmountPath: /etc/kube-flannel/volumes:- name: runhostPath:path: /run/flannel- name: cni-pluginhostPath:path: /opt/cni/bin- name: cnihostPath:path: /etc/cni/net.d- name: flannel-cfgconfigMap:name: kube-flannel-cfg
EOF

应用配置

kubectl apply –f kube-flannel.yml

检验结果

kubectl get pods -n kube-system | grep kube-flannel

在这里插入图片描述
kubectl get pod -n kube-system -o wide

如果有Error或者其他非Running情况：
查看具体报错情况

kubectl describe pod kube-flannel-ds-xxxx -n kube-system

如果是pull image出错：
注意上面kube-flannel.yml用到了2个image，那需要手动拉取

docker pull rancher/mirrored-flannelcni-flannel-cni-plugin:v1.0.0
docker puil quay.io/coreos/flannel:v0.15.1

这里尤其需要注意，K8S把POD分配在了哪个节点，我这里是master，那就必须在master pull 在这里插入图片描述
测试 kubernetes 集群

kubectl create deployment nginx --image=nginx
kubectl expose deployment nginx --port=80 --type=NodePort
kubectl get pod,svc

在这里插入图片描述
集群中的任一节点ip都能访问pod

BUG解决

究极解决方案：删除K8S所有配置直接重装
什么unready基本都能解决

kubeadm reset
rm -rf $HOME/.kube

删除后直接从kubeadm init开始重装

参考文章：
kubernetes 坑人的错误！！！Unable to connect to the server: x509: certificate signed by unknown authority