Kubernetes（k8s）高可用搭建

一、系统基础设置
- 1.1、关闭防火墙
- 1.2、关闭selinux
- 1.3、关闭swap
- 1.4、设置hostname
- 1.5、将桥接的IPv4流量传递到iptables的链
- 1.6、时间同步
- 1.7 配置开启 ipvs 的前提条件
- 1.8、安装iproute-tc和dig工具
二、所有master节点部署keepalived
- 2.1 安装相关包和keepalived
- 2.2配置master节点
- 2.3 启动和检查
三、部署haproxy
- 3.1 安装
- 3.2 配置
- 3.3 启动和检查
四、所有节点安装Docker/kubeadm/kubelet
- 4.1 安装Docker
- 4.2 cri-dockerd安装
- 4.3 添加阿里云YUM软件源
- 4.4 安装kubeadm，kubelet和kubectl
- 4.4 安装kubeadm-cni
五、部署Kubernetes Master
- 5.1 创建kubeadm配置文件
- 5.2 在master1节点执行
六、安装集群网络
- 七、master2节点加入集群
- 7.1 复制密钥及相关文件
- 7.2 master2加入集群
- 7.3master3加入集群
- 7.4检查状态
八、加入Kubernetes Node
- 8.1在node1、node2、node3上执行join命令
- 8.2集群网络重新安装，因为添加了新的node节点
- 8.3检查状态
九、测试kubernetes集群
十、修改 kube-proxy网络模式，并重启kube-proxy
- 1、编辑kube-proxy 配置
- 2、重启kube-proxy
- 3、查看日志
十一、常用命令

一、系统基础设置

1.1、关闭防火墙

systemctl stop firewalld
systemctldisable firewalld

1.2、关闭selinux

sed -i 's/enforcing/disabled/' /etc/selinux/config  # 永久
setenforce 0  # 临时

1.3、关闭swap

swapoff -a  # 临时
sed -ri 's/.*swap.*/#&/' /etc/fstab    # 永久

1.4、设置hostname

hostnamectl set-hostname zxhy-master cat >> /etc/hosts << EOF
192.168.0.15 zxhy-vip
192.168.0.14 zxhy-master
192.168.0.222 zxhy-slave1
192.168.0.77 zxhy-slave2
192.168.0.188 zxhy-slave3
192.168.0.193 zxhy-slave4
192.168.0.227 zxhy-slave5
EOF

1.5、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

1.6、时间同步

yum install ntpdate -y
ntpdate time.windows.com

1.7 配置开启 ipvs 的前提条件

modprobe -- ip_vs
modprobe -- ip_vs_rr
modprobe -- ip_vs_wrr
modprobe -- ip_vs_sh
modprobe -- nf_conntrack

1.8、安装iproute-tc和dig工具

yum install iproute-tc -y
yum -y install bind-utils

二、所有master节点部署keepalived

2.1 安装相关包和keepalived

yum install -y conntrack-tools libseccomp libtool-ltdl
yum install -y keepalived

2.2配置master节点

master1节点配置

cat > /etc/keepalived/keepalived.conf <<EOF 
! Configuration File for keepalivedglobal_defs {router_id k8s
}vrrp_script check_haproxy {script "killall -0 haproxy"interval 3weight -2fall 10rise 2
}vrrp_instance VI_1 {state MASTER interface eth0virtual_router_id 51priority 250advert_int 1authentication {auth_type PASSauth_pass ceb1b3ec013d66163d6ab}virtual_ipaddress {192.168.0.15}track_script {check_haproxy}}
EOF

master2节点配置

cat > /etc/keepalived/keepalived.conf <<EOF 
! Configuration File for keepalivedglobal_defs {router_id k8s
}vrrp_script check_haproxy {script "killall -0 haproxy"interval 3weight -2fall 10rise 2
}vrrp_instance VI_1 {state BACKUPinterface eth0virtual_router_id 51priority 250advert_int 1authentication {auth_type PASSauth_pass ceb1b3ec013d66163d6ab}virtual_ipaddress {192.168.0.14}track_script {check_haproxy}}
EOF

2.3 启动和检查

在三台master节点都执行

# 启动keepalived
$ systemctl start keepalived.service
设置开机启动
$ systemctl enable keepalived.service
# 查看启动状态
$ systemctl status keepalived.service

启动后查看master1的网卡信息

ip a s eth0

如果是云服务器搭建的话，记得云服务器管理平台上申请虚拟IP地址，然后绑定虚拟IP地址到三台主节点服务器上，然后添加相应的网络策略，否侧ping不通虚拟ip

三、部署haproxy

3.1 安装

yum install -y haproxy

3.2 配置

两台master节点的配置均相同，配置中声明了后端代理的两个master节点服务器，指定了haproxy运行的端口为16443等，因此16443端口为集群的入口

cat > /etc/haproxy/haproxy.cfg << EOF
#---------------------------------------------------------------------
# Global settings
#---------------------------------------------------------------------
global# to have these messages end up in /var/log/haproxy.log you will# need to:# 1) configure syslog to accept network log events.  This is done#    by adding the '-r' option to the SYSLOGD_OPTIONS in#    /etc/sysconfig/syslog# 2) configure local2 events to go to the /var/log/haproxy.log#   file. A line like the following can be added to#   /etc/sysconfig/syslog##    local2.*                       /var/log/haproxy.log#log         127.0.0.1 local2chroot      /var/lib/haproxypidfile     /var/run/haproxy.pidmaxconn     4000user        haproxygroup       haproxydaemon # turn on stats unix socketstats socket /var/lib/haproxy/stats
#---------------------------------------------------------------------
# common defaults that all the 'listen' and 'backend' sections will
# use if not designated in their block
#---------------------------------------------------------------------  
defaultsmode                    httplog                     globaloption                  httplogoption                  dontlognulloption http-server-closeoption forwardfor       except 127.0.0.0/8option                  redispatchretries                 3timeout http-request    10stimeout queue           1mtimeout connect         10stimeout client          1mtimeout server          1mtimeout http-keep-alive 10stimeout check           10smaxconn                 3000
#---------------------------------------------------------------------
# kubernetes apiserver frontend which proxys to the backends
#--------------------------------------------------------------------- 
frontend kubernetes-apiservermode                 tcpbind                 *:16443option               tcplogdefault_backend      kubernetes-apiserver    
#---------------------------------------------------------------------
# round robin balancing between the various backends
#---------------------------------------------------------------------
backend kubernetes-apiservermode        tcpbalance     roundrobinserver      zxhy-nacos   192.168.0.14:6443 checkserver      zxhy-redis   192.168.0.77:6443 checkserver      zxhy-mysql   192.168.0.222:6443 check
#---------------------------------------------------------------------
# collection haproxy statistics message
#---------------------------------------------------------------------
listen statsbind                 *:1080stats auth           admin:awesomePasswordstats refresh        5sstats realm          HAProxy\ Statisticsstats uri            /admin?stats
EOF

3.3 启动和检查

三台master都启动

# 设置开机启动
$ systemctl enable haproxy
# 开启haproxy
$ systemctl start haproxy
# 查看启动状态
$ systemctl status haproxy

四、所有节点安装Docker/kubeadm/kubelet

Kubernetes默认CRI（容器运行时）为Docker，因此先安装Docker。

4.1 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-24.0.5.el7
$ systemctl enable docker && systemctl start docker
$ docker --version
Docker version 24.0.5, build e68fc7a

$ cat > /etc/docker/daemon.json << EOF
{"registry-mirrors": ["https://6f09bd673d1d4e8d98dab0ab278fc7c2.mirror.swr.myhuaweicloud.com"],"log-driver": "json-file","log-opts": {"max-size": "100m","max-file": "5"}
}
EOF
# 重启docker服务
systemctl restart docker

4.2 cri-dockerd安装

下载 cri-dockerd 安装包

cd  /opt
wget https://github.com/Mirantis/cri-dockerd/releases/download/v0.3.6/cri-dockerd-0.3.6.20231018204925.877dc6a4-0.el7.x86_64.rpm

安装服务

yum install -y cri-dockerd-0.3.6.20231018204925.877dc6a4-0.el7.x86_64.rpm
vim /usr/lib/systemd/system/cri-docker.service
#添加镜像源
--pod-infra-container-image=registry.aliyuncs.com/google_containers/pause:3.7systemctl daemon-reload
vim /usr/lib/systemd/system/cri-docker.socket

查看服务启动状态

# 设置开机启动
$ systemctl enable cri-docker
# 开启cri-docker
$ systemctl start cri-docker
# 查看启动状态
$ systemctl status cri-docker

查看CRI服务是否被禁止

vi /etc/containerd/config.toml 
#如果disabled_plugins中包含cri，删除“cri”即可
#disabled_plugins = [“cri”]
disabled_plugins = []

重启容器运行时

systemctl restart containerd

4.3 添加阿里云YUM软件源

$ 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

4.4 安装kubeadm，kubelet和kubectl

由于版本更新频繁，这里指定版本号部署：

$ yum install -y kubelet-1.24.7 kubeadm-1.24.7 kubectl-1.24.7
$ systemctl enable kubelet

4.4 安装kubeadm-cni

network plugin is not ready: cni config uninitialized

五、部署Kubernetes Master

5.1 创建kubeadm配置文件

在具有vip的master上操作，这里为master1

$ mkdir /usr/local/kubernetes/manifests -p$ cd /usr/local/kubernetes/manifests/$ vi kubeadm-config.yamlapiVersion: kubeadm.k8s.io/v1beta3
kind: InitConfiguration
bootstrapTokens:
- groups:- system:bootstrappers:kubeadm:default-node-tokentoken: abcdef.0123456789abcdefttl: 24h0m0susages:- signing- authentication
localAPIEndpoint:advertiseAddress: 192.168.0.14bindPort: 6443
nodeRegistration:criSocket: unix:///var/run/cri-dockerd.sockimagePullPolicy: IfNotPresentname: zxhy-nacostaints: null
---
apiServer:certSANs:- zxhy-nacos- zxhy-redis- zxhy-mysql- zxhy-vip- 192.168.0.14- 192.168.0.222- 192.168.0.77- 192.168.0.15- 127.0.0.1extraArgs:authorization-mode: Node,RBACtimeoutForControlPlane: 4m0s
apiVersion: kubeadm.k8s.io/v1beta3
certificatesDir: /etc/kubernetes/pki
clusterName: kubernetes
controlPlaneEndpoint: "zxhy-vip:16443"
controllerManager: {}
dns: {}
etcd:local:    dataDir: /var/lib/etcd
imageRepository: registry.aliyuncs.com/google_containers
kind: ClusterConfiguration
kubernetesVersion: v1.24.7
networking: dnsDomain: cluster.local  podSubnet: 10.244.0.0/16serviceSubnet: 10.1.0.0/16
scheduler: {}

5.2 在master1节点执行

$ kubeadm init --config kubeadm-config.yamlexport KUBECONFIG=/etc/kubernetes/admin.conf

按照提示配置环境变量，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
$ kubectl get nodes
$ kubectl get pods -n kube-system

按照提示保存以下内容，一会要使用：

kubeadm join zxhy-vip:16443 --token gp4qgj.3x8wal0o2gmbcpis --discovery-token-ca-cert-hash sha256:af5fe3bb4f2ada51967c34053e94ed4c703287e3e26487d6d8dbe450a2550013 --cri-socket=unix:///var/run/cri-dockerd.sock
#如果忘记复制，也可以利用这个命令重新生成下加入命令
kubeadm token create --print-join-command

六、安装集群网络

从官方地址获取到flannel的yaml，在master1上执行

mkdir /usr/local/kubernetes/manifests/flannel
cd /usr/local/kubernetes/manifests/flannel
wget -c https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml

安装flannel网络

kubectl apply -f kube-flannel.yml

检查

kubectl get pods -n kube-system

七、master2节点加入集群

7.1 复制密钥及相关文件

从master1复制密钥及相关文件到master2

# ssh root@192.168.0.222 mkdir -p /etc/kubernetes/pki/etcd# scp /etc/kubernetes/admin.conf root@192.168.0.222:/etc/kubernetes# scp /etc/kubernetes/pki/{ca.*,sa.*,front-proxy-ca.*} root@192.168.0.222:/etc/kubernetes/pki# scp /etc/kubernetes/pki/etcd/ca.* root@192.168.0.222:/etc/kubernetes/pki/etcd

7.2 master2加入集群

执行在master1上init后输出的join命令,需要带上参数--control-plane表示把master控制节点加入集群

kubeadm join zxhy-vip:16443 --token gp4qgj.3x8wal0o2gmbcpis --discovery-token-ca-cert-hash sha256:af5fe3bb4f2ada51967c34053e94ed4c703287e3e26487d6d8dbe450a2550013 --control-plane --cri-socket=unix:///var/run/cri-dockerd.sock

按照提示配置环境变量，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
$ kubectl get nodes
$ kubectl get pods -n kube-system

7.3master3加入集群

跟节点2同样的操作

7.4检查状态

kubectl get nodekubectl get pods --all-namespaces

八、加入Kubernetes Node

8.1在node1、node2、node3上执行join命令

向集群添加新节点，执行在kubeadm init输出的kubeadm join命令：

kubeadm join zxhy-vip:16443 --token gp4qgj.3x8wal0o2gmbcpis --discovery-token-ca-cert-hash sha256:af5fe3bb4f2ada51967c34053e94ed4c703287e3e26487d6d8dbe450a2550013 --cri-socket=unix:///var/run/cri-dockerd.sock

8.2集群网络重新安装，因为添加了新的node节点

所有节点加入完成后安装flannel网络

#进入flannel网络
cd /usr/local/kubernetes/manifests/flannel
#删除之前的网络
kubectl delete -f kube-flannel.yml 
#重新初始化的网络
kubectl apply -f kube-flannel.yml

8.3检查状态

kubectl get nodekubectl get pods --all-namespaces

九、测试kubernetes集群

在Kubernetes集群中创建一个pod，验证是否正常运行：

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

十、修改 kube-proxy网络模式，并重启kube-proxy

1、编辑kube-proxy 配置

kubectl edit cm kube-proxy -n kube-system

将mode: iptables 修改成 mode: ipvs

2、重启kube-proxy

kubectl get pod -n kube-system | grep kube-proxy |awk ‘{system(“kubectl delete pod “$1” -n kube-system”)}’

3、查看日志

kubectl logs -f -n kube-system kube-proxy-62fk7

十一、常用命令

#进入容器
kubectl exec -it nacos-0 bash
#查看dns服务器
cat /etc/resolv.conf
#查看无头服务访问地址
dig @10.1.0.10 nacos-headless.default.svc.cluster.local