k8s 基于kubeadm搭建高可用集群

1.安装配置负载均衡工具

1.1 配置 haproxy （主节点都需要配置）
1.1.1 下载 haproxy

yum -y install haproxy
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1.1.2 修改 haproxy配置文件

#---------------------------------------------------------------------
# Example configuration for a possible web application.  See the
# full configuration options online.
#
#   http://haproxy.1wt.eu/download/1.4/doc/configuration.txt
#
#---------------------------------------------------------------------

#---------------------------------------------------------------------
# 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 local2

    chroot      /var/lib/haproxy
    pidfile     /var/run/haproxy.pid
    maxconn     4000
    user        haproxy
    group       haproxy
    daemon

    # turn on stats unix socket
    stats socket /var/lib/haproxy/stats

#---------------------------------------------------------------------
# common defaults that all the 'listen' and 'backend' sections will
# use if not designated in their block
#---------------------------------------------------------------------
defaults
    mode                    http
    log                     global
    option                  httplog
    option                  dontlognull
    option http-server-close
    option forwardfor       except 127.0.0.0/8
    option                  redispatch
    retries                 3
    timeout http-request    10s
    timeout queue           1m
    timeout connect         10s
    timeout client          1m
    timeout server          1m
    timeout http-keep-alive 10s
    timeout check           10s
    maxconn                 3000

#---------------------------------------------------------------------
# main frontend which proxys to the backends
#---------------------------------------------------------------------
frontend  k8s-apiserver   ## 配置master的监听
    mode tcp
    bind *:9443  ## 监听9443端口（这个端口用于kubeadm 初始化需要）
    acl url_static       path_beg       -i /static /images /javascript /stylesheets
    acl url_static       path_end       -i .jpg .gif .png .css .js

    use_backend static          if url_static
    default_backend             k8s-apiserver  ##  backend k8s-apiserver

#---------------------------------------------------------------------
# static backend for serving up images, stylesheets and such
#---------------------------------------------------------------------
backend static    ##这个对于我们配置 k8s 无关
    balance     roundrobin
    server      static 127.0.0.1:4331 check

#---------------------------------------------------------------------
# round robin balancing between the various backends
#---------------------------------------------------------------------
backend k8s-apiserver
    mode        tcp   # 模式tcp
    balance     roundrobin  # 采用轮询的负载算法
    server  k8s-master1 192.168.34.7:6443 check  ##k8s管理节点的aipserver
    server  k8s-master2 192.168.34.9:6443 check  ##k8s管理节点的aipserver
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1.1.3 重启 haproxy

systemctl restart haproxy
systemctl enable haproxy
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1.2 配置 keepalived（主节点都需要配置）
1.2.1 下载 keepalived

yum -y install keepalived
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1.2.2 修改 keepalived配置文件
监听haproxy脚本

#!/bin/bash
A=`ps -C haproxy --no-header |wc -l`

if [ $A -eq 0 ];then
  systemctl start haproxy
  sleep 3
    if [ `ps -C haproxy --no-header |wc -l` -eq 0 ];then
      systemctl stop keepalived.service
    fi
fi
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! Configuration File for keepalived


vrrp_script chk_http_prot {
    script "/etc/keepalived/check_haproxy.sh"
    fall 2
    rise 10
    interval 2  # 每2秒执行一次检测
    weight 2  # 权重
}

global_defs {
   router_id k8s-master2   ##当前设备的hostname
}

vrrp_instance VI_1 {
    state MASTER  ##表示主节点
    interface ens192  ##对应本机的网卡
    virtual_router_id 1  ## id设为相同，表示是同一个虚拟路由组（所有的master节点这个要一样）
    priority 80   ##权重
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    virtual_ipaddress {
        192.168.34.100  ##虚拟ip（vip） 
    }
   track_script {
     chk_http_prot    
   }
}
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1.2.3 重启 keepalived

systemctl restart keepalived
systemctl enable keepalived
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2. 安装kubernetes（k8s）

2.1 k8s安装配置
所有节点都需要安装 kubeadm 、kubelet、kubectl（kubectl 的安装防止后期从节点转主节点）
2.2 kubeadm 启动加入集群

## kubeadm init --control-plane-endpoint (keepalived的虚拟ip【vip】):(haproxy的监听端口) --upload-certs --v=6 --image-repository registry.aliyuncs.com/google_containers  --pod-network-cidr=10.244.0.0/16 --kubernetes-version 1.23.5
kubeadm init --control-plane-endpoint 192.168.34.100:9443 --upload-certs --v=6 --image-repository registry.aliyuncs.com/google_containers  --pod-network-cidr=10.244.0.0/16 --kubernetes-version 1.23.5
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执行后得到下边图片

2.2.1 根据 2.2 生成的命令后得到这个命令，然后这个命令加入其他主节点

kubeadm join 192.168.34.100:9443 --token 90oq2o.vjug3xrqgx1bunfv \
	--discovery-token-ca-cert-hash sha256:a2c4ea68b869f43c0fe4ee093c7190d20a7af2d536278992d7c7dcbb05b757e3 \
	--control-plane --certificate-key 5275b355db7f39d797d6fce756644ee777ba28ec3374b8d4ccfac9b78254cd21
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2.2.2 根据 2.2 生成的命令后得到这个命令，然后这个命令加入其他工作节点

kubeadm join 192.168.34.100:9443 --token 90oq2o.vjug3xrqgx1bunfv \
	--discovery-token-ca-cert-hash sha256:a2c4ea68b869f43c0fe4ee093c7190d20a7af2d536278992d7c7dcbb05b757e3 
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2.3 查看 k8s 集群

kubectl get nodes
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2.3.1 可以看到我们的节点显示 NotReady ，这种情况是因为我们没有配置网络
kube-flannel.yml 插件安装