kubeadm部署高可用版Kubernetes1.21[基于centos7.6]

1. 基础环境规划：

主机名	IP地址	节点说明
k8s-node01	192.168.1.154	node1节点
k8s-node02	192.168.1.155	node2节点
master01	192.168.1.151	master1节点
master02	192.168.1.152	master2节点
master03	192.168.1.153	master3节点
虚拟vip	192.168.1.160	虚拟IP

​

docker配置信息：

配置信息	备注
系统版本	CentOS Linux release 7.6.1810
Docker版本	20.10
Pod网段	172.168.0.0/12
Service网段	10.96.0.0/12

注意：公有云上搭建VIP是公有云的负载均衡的IP，比如阿里云的内网SLB的地址，腾讯云内网ELB的地址

#花里胡哨的美化配置：
#命令行优化：
echo "export PS1='\[\033[01;31m\]\u\[\033[00m\]@\[\033[01;32m\]\h\[\033[00m\][\[\033[01;33m\]\t\[\033[00m\]]:\[\033[01;34m\]\w\[\033[00m\]$ '" >>/etc/profile
source /etc/profile

#历史记录优化：
export HISTTIMEFORMAT='%F %T '
echo "export HISTTIMEFORMAT='%F %T '" >>/etc/profile
source /etc/profile

2.前期准备工作

2.1 所有节点hosts配置

#每个节点设置主机名：
hostnamectl set-hostname [主机名]
如：
hostnamectl set-hostname k8s-master01

#所有节点配置hosts，修改/etc/hosts如下：
[root@k8s-master01 ~]# cat /etc/hosts
192.168.1.151 k8s-master01
192.168.1.152 k8s-master02
192.168.1.153 k8s-master03
192.168.1.160 k8s-master-lb # 如果不是高可用集群，该IP为Master01的IP
192.168.1.154 k8s-node01
192.168.1.155 k8s-node02

cat <<EOF > /etc/hosts
127.0.0.1   localhost localhost.localdomain localhost4 localhost4.localdomain4
::1         localhost localhost.localdomain localhost6 localhost6.localdomain6
192.168.1.151 k8s-master01
192.168.1.152 k8s-master02
192.168.1.153 k8s-master03
192.168.1.160 k8s-master-lb
192.168.1.154 k8s-node01
192.168.1.155 k8s-node02
EOF

#命令行优化：
echo "export PS1='\[\033[01;31m\]\u\[\033[00m\]@\[\033[01;32m\]\h\[\033[00m\][\[\033[01;33m\]\t\[\033[00m\]]:\[\033[01;34m\]\w\[\033[00m\]$ '" >>/etc/profile
source /etc/profile

#历史记录优化：
export HISTTIMEFORMAT='%F %T '
echo "export HISTTIMEFORMAT='%F %T '" >>/etc/profile
source /etc/profile

2.2 所有节点源配置[centos7]

mv /etc/yum.repos.d/* /root
cd /etc/yum.repos.d/
curl -o /etc/yum.repos.d/CentOS-Base.repo https://mirrors.aliyun.com/repo/Centos-7.repo
yum install -y yum-utils device-mapper-persistent-data lvm2
yum-config-manager --add-repo https://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo

cat <<EOF > /etc/yum.repos.d/kubernetes.repo
[kubernetes]
name=Kubernetes
baseurl=https://mirrors.aliyun.com/kubernetes/yum/repos/kubernetes-el7-x86_64/
enabled=1
gpgcheck=1
repo_gpgcheck=1
gpgkey=https://mirrors.aliyun.com/kubernetes/yum/doc/yum-key.gpg https://mirrors.aliyun.com/kubernetes/yum/doc/rpm-package-key.gpg
EOF
sed -i -e '/mirrors.cloud.aliyuncs.com/d' -e '/mirrors.aliyuncs.com/d' /etc/yum.repos.d/CentOS-Base.repo
yum clean all
yum install -y epel-release 

#安装必备工具：
#必备工具安装
yum install wget jq psmisc vim net-tools telnet yum-utils device-mapper-persistent-data lvm2 git -y

2.3 所有节点优化

#所有节点关闭防火墙、selinux、dnsmasq、swap。服务器配置如下：
systemctl disable --now firewalld
systemctl disable --now dnsmasq
systemctl disable --now NetworkManager

setenforce 0
sed -i 's#SELINUX=enforcing#SELINUX=disabled#g' /etc/sysconfig/selinux
sed -i 's#SELINUX=enforcing#SELINUX=disabled#g' /etc/selinux/config

#关闭swap分区
swapoff -a && sysctl -w vm.swappiness=0
sed -ri '/^[^#]*swap/s@^@#@' /etc/fstab

#安装ntpdate
rpm -ivh http://mirrors.wlnmp.com/centos/wlnmp-release-centos.noarch.rpm

#添加计划任务
yum install -y ntpdate
echo '*/5 * * * * ntpdate cn.pool.ntp.org' >>/var/spool/cron/root
systemctl restart crond
ntpdate time2.aliyun.com

#所有节点同步时间。时间同步配置如下：
ln -sf /usr/share/zoneinfo/Asia/Shanghai /etc/localtime
echo 'Asia/Shanghai' >/etc/timezone
ntpdate time2.aliyun.com
# 加入到crontab
*/5 * * * * /usr/sbin/ntpdate time2.aliyun.com

#limit优化
ulimit -SHn 65535

cat <<EOF >> /etc/security/limits.conf
* soft nofile 655360
* hard nofile 131072
* soft nproc 655350
* hard nproc 655350
* soft memlock unlimited
* hard memlock unlimited
EOF

2.4 配置免密[中控机操作]

#Master01节点免密钥登录其他节点，安装过程中生成配置文件和证书均在Master01上操作，集群管理也在Master01上操作，阿里云或者AWS上需要单独一台kubectl服务器。密钥配置如下：
cd /root
ssh-keygen -t rsa
for i in k8s-master01 k8s-master02 k8s-master03 k8s-node01 k8s-node02;do ssh-copy-id -i .ssh/id_rsa.pub $i;done

2.5 升级内核 [中控机操作]

#下载安装所有的源码文件
cd /root/
git clone https://github.com/dotbalo/k8s-ha-install.git

#如果无法下载请使用下面的重试：
git clone https://gitee.com/dukuan/k8s-ha-install.git

# 在master01节点下载内核,并缓存 [所有机器升级]
#CentOS7需要升级系统，CentOS8可以按需升级系统
yum update -y --exclude=kernel* && reboot

# 内核配置
#CentOS7 需要升级内核至4.18+，本地升级的版本为4.19

cd /root
wget http://193.49.22.109/elrepo/kernel/el7/x86_64/RPMS/kernel-ml-devel-4.19.12-1.el7.elrepo.x86_64.rpm
wget http://193.49.22.109/elrepo/kernel/el7/x86_64/RPMS/kernel-ml-4.19.12-1.el7.elrepo.x86_64.rpm

#从master01节点传到其他节点：
for i in k8s-master02 k8s-master03 k8s-node01 k8s-node02;do scp kernel-ml-4.19.12-1.el7.elrepo.x86_64.rpm kernel-ml-devel-4.19.12-1.el7.elrepo.x86_64.rpm $i:/root/ ; done

#所有节点安装内核
cd /root && yum localinstall -y kernel-ml*

#所有节点更改内核启动顺序
grub2-set-default 0 && grub2-mkconfig -o /etc/grub2.cfg
grubby --args="user_namespace.enable=1" --update-kernel="$(grubby --default-kernel)"

#检查默认内核是不是4.19
root@k8s-master01[17:05:33]:~$ grubby --default-kernel
/boot/vmlinuz-4.19.12-1.el7.elrepo.x86_64 

#所有节点重启，然后检查内核是不是4.19
 root@k8s-master01[17:09:20]:~$ grubby --default-kernel
/boot/vmlinuz-4.19.12-1.el7.elrepo.x86_64 

#如果是，则说明内核配置正确

2.6 所有节点安装ipvsadm

yum install ipvsadm ipset sysstat conntrack libseccomp -y 

#所有节点配置ipvs模块，在内核4.19+版本nf_conntrack_ipv4已经改为nf_conntrack， 4.18以下使用nf_conntrack_ipv4即可： 

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

#创建 /etc/modules-load.d/ipvs.conf 并加入以下内容：
cat >/etc/modules-load.d/ipvs.conf <<EOF
ip_vs
ip_vs_lc
ip_vs_wlc
ip_vs_rr
ip_vs_wrr
ip_vs_lblc
ip_vs_lblcr
ip_vs_dh
ip_vs_sh
ip_vs_fo
ip_vs_nq
ip_vs_sed
ip_vs_ftp
ip_vs_sh
nf_conntrack
ip_tables
ip_set
xt_set
ipt_set
ipt_rpfilter
ipt_REJECT
ipip
EOF

#设置为开机启动
systemctl enable --now systemd-modules-load.service

2.7 k8s内核优化

#开启一些k8s集群中必须的内核参数，所有节点配置k8s内核：
cat <<EOF > /etc/sysctl.d/k8s.conf
net.ipv4.ip_forward = 1
net.bridge.bridge-nf-call-iptables = 1
net.bridge.bridge-nf-call-ip6tables = 1
fs.may_detach_mounts = 1
vm.overcommit_memory=1
vm.panic_on_oom=0
fs.inotify.max_user_watches=89100
fs.file-max=52706963
fs.nr_open=52706963
net.netfilter.nf_conntrack_max=2310720

net.ipv4.tcp_keepalive_time = 600
net.ipv4.tcp_keepalive_probes = 3
net.ipv4.tcp_keepalive_intvl =15
net.ipv4.tcp_max_tw_buckets = 36000
net.ipv4.tcp_tw_reuse = 1
net.ipv4.tcp_max_orphans = 327680
net.ipv4.tcp_orphan_retries = 3
net.ipv4.tcp_syncookies = 1
net.ipv4.tcp_max_syn_backlog = 16384
net.ipv4.ip_conntrack_max = 65536
net.ipv4.tcp_max_syn_backlog = 16384
net.ipv4.tcp_timestamps = 0
net.core.somaxconn = 16384
EOF
sysctl --system

#所有节点配置完内核后，重启服务器，保证重启后内核依旧加载

reboot
lsmod | grep --color=auto -e ip_vs -e nf_conntrack

#重启后结果如下代表正常：
root@k8s-master01[17:19:15]:~$ lsmod | grep --color=auto -e ip_vs -e nf_conntrack
ip_vs_ftp              16384  0
nf_nat                 32768  1 ip_vs_ftp
ip_vs_sed              16384  0
ip_vs_nq               16384  0
ip_vs_fo               16384  0
ip_vs_sh               16384  0
ip_vs_dh               16384  0
ip_vs_lblcr            16384  0
ip_vs_lblc             16384  0
ip_vs_wrr              16384  0
ip_vs_rr               16384  0
ip_vs_wlc              16384  0
ip_vs_lc               16384  0
ip_vs                 151552  24 ip_vs_wlc,ip_vs_rr,ip_vs_dh,ip_vs_lblcr,ip_vs_sh,ip_vs_fo,ip_vs_nq,ip_vs_lblc,ip_vs_wrr,ip_vs_lc,ip_vs_sed,ip_vs_ftp
nf_conntrack          143360  2 nf_nat,ip_vs
nf_defrag_ipv6         20480  1 nf_conntrack
nf_defrag_ipv4         16384  1 nf_conntrack
libcrc32c              16384  4 nf_conntrack,nf_nat,xfs,ip_vs

3. 基本组件安装

本节主要安装的是集群中用到的各种组件，比如Docker-ce、Kubernetes各组件等。

3.1 所有节点安装 docker-ce 20.10

yum install -y docker-ce-20.10.6-* docker-ce-cli-20.10.6-*.x86_64
rm -f /etc/docker/*
sudo mkdir -p /etc/docker
sudo tee /etc/docker/daemon.json <<-'EOF'
{
  "registry-mirrors": ["https://ajvcw8qn.mirror.aliyuncs.com"],
  "exec-opts": ["native.cgroupdriver=systemd"]
}
EOF
sudo systemctl daemon-reload
sudo systemctl restart docker
systemctl enable --now  docker.service

3.2 所有机器安装k8s组件kubeadm

yum list kubeadm.x86_64 --showduplicates | sort -r

#所有节点安装最新版本kubeadm：
yum install kubeadm-1.21* kubelet-1.21* kubectl-1.21* -y

#默认配置的pause镜像使用gcr.io仓库，国内可能无法访问，所以这里配置Kubelet使用阿里云的pause镜像
cat >/etc/sysconfig/kubelet<<EOF
KUBELET_EXTRA_ARGS="--cgroup-driver=systemd --pod-infra-container-image=registry.cn-hangzhou.aliyuncs.com/google_containers/pause-amd64:3.2"
EOF

#设置开机启动
systemctl daemon-reload
systemctl enable --now kubelet

3.3 安装高可用组件[master相关服务器执行]

注意：如果不是高可用集群，haproxy和keepalived无需安装）

公有云要用公有云自带的负载均衡，比如阿里云的SLB，腾讯云的ELB，用来替代haproxy和keepalived，因为公有云大部分都是不支持keepalived的，另外如果用阿里云的话，kubectl控制端不能放在master节点，推荐使用腾讯云，因为阿里云的slb有回环的问题，也就是slb代理的服务器不能反向访问SLB，但是腾讯云修复了这个问题。

#所有Master节点通过yum安装HAProxy和KeepAlived：
root@k8s-master01[17:44:47]:~$  yum install keepalived haproxy -y

#配置HAProxy：

#所有Master节点配置HAProxy（详细配置参考HAProxy文档，所有Master节点的HAProxy配置相同）：

mkdir /etc/haproxy
cat >/etc/haproxy/haproxy.cfg<<"EOF"
global
 maxconn 2000
 ulimit-n 16384
 log 127.0.0.1 local0 err
 stats timeout 30s

defaults
 log global
 mode http
 option httplog
 timeout connect 5000
 timeout client 50000
 timeout server 50000
 timeout http-request 15s
 timeout http-keep-alive 15s

frontend monitor-in
 bind *:33305
 mode http
 option httplog
 monitor-uri /monitor

frontend k8s-master
 bind 0.0.0.0:16443
 bind 127.0.0.1:16443
 mode tcp
 option tcplog
 tcp-request inspect-delay 5s
 default_backend k8s-master

backend k8s-master
 mode tcp
 option tcplog
 option tcp-check
 balance roundrobin
 default-server inter 10s downinter 5s rise 2 fall 2 slowstart 60s maxconn 250 maxqueue 256 weight 100
 server k8s-master01  192.168.1.151:6443 check
 server k8s-master02  192.168.1.152:6443 check
 server k8s-master03  192.168.1.153:6443 check
EOF

#所有Master节点配置KeepAlived，配置不一样，注意区分
#[root@k8s-master01 pki]# vim /etc/keepalived/keepalived.conf ，注意每个节点的IP和网卡（interface参数）

#注意修改配置，下面IP替换为master的IP地址：
server k8s-master01  192.168.1.151:6443 check
server k8s-master02  192.168.1.152:6443 check
server k8s-master03  192.168.1.153:6443 check

#配置keepalived
#所有Master节点配置KeepAlived，配置不一样，注意区分
#每台服务器 优先级必须不同 priority 100 其他机器设置为 99 98
#master01 配置：

[root@k8s-master01 pki]# mkdir -p /etc/keepalived
[root@k8s-master01 pki]# cat >/etc/keepalived/keepalived.conf<<"EOF"
! Configuration File for keepalived
global_defs {
   router_id LVS_DEVEL
script_user root
   enable_script_security
}
vrrp_script chk_apiserver {
   script "/etc/keepalived/check_apiserver.sh"
   interval 5
   weight -5
   fall 2
rise 1
}
vrrp_instance VI_1 {
   state MASTER
   interface eth0
   mcast_src_ip 192.168.1.151
   virtual_router_id 51
   priority 101
   advert_int 2
   authentication {
       auth_type PASS
       auth_pass K8SHA_KA_AUTH
   }
   virtual_ipaddress {
       192.168.1.160
   }
   track_script {
      chk_apiserver
   }
}
EOF

#Master02 配置：
[root@k8s-master02 pki]# cat >/etc/keepalived/keepalived.conf<<"EOF"
! Configuration File for keepalived
global_defs {
   router_id LVS_DEVEL
script_user root
   enable_script_security
}
vrrp_script chk_apiserver {
   script "/etc/keepalived/check_apiserver.sh"
  interval 5
   weight -5
   fall 2
rise 1
}
vrrp_instance VI_1 {
   state BACKUP
   interface eth0
   mcast_src_ip 192.168.1.152
   virtual_router_id 51
   priority 100
   advert_int 2
   authentication {
       auth_type PASS
       auth_pass K8SHA_KA_AUTH
   }
   virtual_ipaddress {
       192.168.1.160
   }
   track_script {
      chk_apiserver
   }
}
EOF

#Master03 配置：
[root@k8s-master03 pki]# cat >/etc/keepalived/keepalived.conf<<"EOF"
! Configuration File for keepalived
global_defs {
   router_id LVS_DEVEL
script_user root
   enable_script_security
}
vrrp_script chk_apiserver {
   script "/etc/keepalived/check_apiserver.sh"
 interval 5
   weight -5
   fall 2
rise 1
}
vrrp_instance VI_1 {
   state BACKUP
   interface eth0
   mcast_src_ip 192.168.1.153
   virtual_router_id 51
   priority 100
   advert_int 2
   authentication {
       auth_type PASS
       auth_pass K8SHA_KA_AUTH
   }
   virtual_ipaddress {
       192.168.1.160
   }
EOF

#快捷办法[变量获取本机IP]：
host=$(hostname -i)
cat >/etc/keepalived/keepalived.conf<<EOF
! Configuration File for keepalived
global_defs {
   router_id LVS_DEVEL
script_user root
   enable_script_security
}
vrrp_script chk_apiserver {
   script "/etc/keepalived/check_apiserver.sh"
   interval 5
   weight -5
   fall 2
rise 1
}
vrrp_instance VI_1 {
   state MASTER
   interface eth0
   mcast_src_ip $(hostname -i)
   virtual_router_id 51
   priority 101
   advert_int 2
   authentication {
       auth_type PASS
       auth_pass K8SHA_KA_AUTH
   }
   virtual_ipaddress {
       192.168.1.160
   }
   track_script {
      chk_apiserver
   }
}
EOF

3.4 健康检查配置[所有master服务器添加健康检查脚本]

cat > /etc/keepalived/check_apiserver.sh <<"EOF"
#!/bin/bash
err=0
for k in $(seq 1 3)
do
   check_code=$(pgrep haproxy)
   if [[ $check_code == "" ]]; then
       err=$(expr $err + 1)
       sleep 1
       continue
   else
       err=0
       break
   fi
done

if [[ $err != "0" ]]; then
   echo "systemctl stop keepalived"
   /usr/bin/systemctl stop keepalived
   exit 1
else
   exit 0
fi
EOF

chmod +x /etc/keepalived/check_apiserver.sh

3.5 启动haproxy和keepalived[每台master启用]

systemctl daemon-reload
systemctl enable --now haproxy
systemctl enable --now keepalived

3.6 测试haproxy与keepalived是否正常

重要：如果安装了keepalived和haproxy，需要测试keepalived是否是正常的
所以这里需要测试VIP是否通

ping 192.168.1.160 -c 4

root@k8s-master01[18:17:06]:~$ ping 192.168.1.160 -c 4
PING 192.168.1.160 (192.168.1.160) 56(84) bytes of data.
64 bytes from 192.168.1.160: icmp_seq=1 ttl=64 time=0.045 ms 

root@k8s-master02[18:17:10]:~$ ping 192.168.1.160 -c 4
PING 192.168.1.160 (192.168.1.160) 56(84) bytes of data.
64 bytes from 192.168.1.160: icmp_seq=1 ttl=64 time=1.00 ms 

root@k8s-master03[18:17:13]:~$ ping 192.168.1.160 -c 4
PING 192.168.1.160 (192.168.1.160) 56(84) bytes of data.
64 bytes from 192.168.1.160: icmp_seq=1 ttl=64 time=2.48 ms

telnet测试：
root@k8s-master03[18:19:51]:~$ telnet 192.168.1.160 16443
Trying 192.168.1.160...
Connected to 192.168.1.160.
Escape character is '^]'.
Connection closed by foreign host. 

注意： 如果ping不通且telnet没有出现 ] ，则认为VIP不可以，不可在继续往下执行，需要排查keepalived的问题，比如防火墙和selinux，haproxy和keepalived的状态，监听端口等
所有节点查看防火墙状态必须为disable和inactive：systemctl status firewalld
所有节点查看selinux状态，必须为disable：getenforce
master节点查看haproxy和keepalived状态：systemctl status keepalived haproxy
master节点查看监听端口：netstat -lntp

排查思路：
keepalived的问题，比如防火墙和selinux，haproxy和keepalived的状态，监听端口等
所有节点查看防火墙状态必须为disable和inactive：systemctl status firewalld
所有节点查看selinux状态，必须为disable：getenforce
master节点查看haproxy和keepalived状态：systemctl status keepalived haproxy
master节点查看监听端口：netstat -lntp

4.0 kubernetes集群初始化

官方初始化文档：

https://kubernetes.io/docs/setup/production-environment/tools/kubeadm/high-availability/

Master01节点创建 kubeadm-config.yaml 配置文件如下：
Master01：（# 注意，如果不是高可用集群，192.168.1.160:16443改为master01的地址，16443改为apiserver的端口，默认是6443，注意更改v1.18.5自己服务器kubeadm的版本：kubeadm version）

#查看办法：
kubectl version
root@k8s-master01[18:25:48]:~$ kubectl version
Client Version: version.Info{Major:"1", Minor:"21", GitVersion:"v1.21.0", GitCommit:"cb303e613a121a29364f75cc67d3d580833a7479", GitTreeState:"clean", BuildDate:"2021-04-08T16:31:21Z", GoVersion:"go1.16.1", Compiler:"gc", Platform:"linux/amd64"} 

因为安装的版本是 GitVersion:"v1.21.0"
下面的yaml文件中的对应版本需要改为  v1.21.0

cat kubeadm-config.yaml

apiVersion: kubeadm.k8s.io/v1beta2
bootstrapTokens:
- groups:
 - system:bootstrappers:kubeadm:default-node-token
 token: 7t2weq.bjbawausm0jaxury
 ttl: 24h0m0s
 usages:
 - signing
 - authentication
kind: InitConfiguration
localAPIEndpoint:
 advertiseAddress: 192.168.1.151
 bindPort: 6443
nodeRegistration:
 criSocket: /var/run/dockershim.sock
 name: k8s-master01
 taints:
 - effect: NoSchedule
   key: node-role.kubernetes.io/master
---
apiServer:
 certSANs:
 - 192.168.1.160
 timeoutForControlPlane: 4m0s
apiVersion: kubeadm.k8s.io/v1beta2
certificatesDir: /etc/kubernetes/pki
clusterName: kubernetes
controlPlaneEndpoint: 192.168.1.160:16443
controllerManager: {}
dns:
 type: CoreDNS
etcd:
 local:
   dataDir: /var/lib/etcd
imageRepository: registry.cn-hangzhou.aliyuncs.com/google_containers
kind: ClusterConfiguration
kubernetesVersion: v1.21.0
networking:
 dnsDomain: cluster.local
 podSubnet: 172.16.0.0/12
 serviceSubnet: 192.168.0.0/16
scheduler: {}

更新kubeadm文件[只有master01执行] 注意：需要修改的地方是 网段和版本 网段可以保持默认，但是版本建议与当前安装版本一致 kubeadm-config.yaml中的网段需要修改为 172.168.0.0/12 通过grep 'podSubnet:' /root/kubeadm-config.yaml

#更新kubeadm文件: kubeadm-config.yaml

kubeadm config migrate --old-config kubeadm-config.yaml --new-config new.yaml

#将new.yaml文件复制到其他master节点，之后所有Master节点提前下载镜像，可以节省初始化时间：
for i in k8s-master02 k8s-master03; do scp new.yaml $i:/root/; done

#在其他master节点提前下载镜像，用于解决初始化时间
kubeadm config images pull --config /root/new.yaml
systemctl enable --now kubelet

#执行kubeadm config images pull --config /root/new.yaml如果出现如下报错
[config/images] Pulled registry.cn-hangzhou.aliyuncs.com/google_containers/pause:3.4.1
[config/images] Pulled registry.cn-hangzhou.aliyuncs.com/google_containers/etcd:3.4.13-0
failed to pull image "registry.cn-hangzhou.aliyuncs.com/google_containers/coredns/coredns:v1.8.0": output: Error response from daemon: manifest for registry.cn-hangzhou.aliyuncs.com/google_containers/coredns/coredns:v1.8.0 not found: manifest unknown: manifest unknown
, error: exit status 1
To see the stack trace of this error execute with --v=5 or higher 

#coredns如果没有成功
出现ImagePullBackOff：
coredns-57d4cbf879-gnh6j        0/1     ImagePullBackOff   0          6m
coredns-57d4cbf879-z79bt        0/1     ImagePullBackOff   0          6m

#请所有节点执行，用于下载镜像即可：
docker pull registry.cn-beijing.aliyuncs.com/dotbalo/coredns:1.8.0
docker tag registry.cn-beijing.aliyuncs.com/dotbalo/coredns:1.8.0 registry.cn-hangzhou.aliyuncs.com/google_containers/coredns/coredns:v1.8.0

#再次查看就会自动拉起
coredns-57d4cbf879-gnh6j                  1/1     Running   0          16h
coredns-57d4cbf879-z79bt                  1/1     Running   0          16h

所有节点设置开机自启动kubelet systemctl daemon-reload systemctl enable --now kubelet

4.2 master01初始化

Master01节点初始化，初始化以后会在/etc/kubernetes目录下生成对应的证书和配置文件，之后其他Master节点加入Master01即可：

#master01节点执行初始化：
kubeadm init --config /root/new.yaml --upload-certs

#如果初始化失败，重置后再次初始化，命令如下：
kubeadm reset -f ; ipvsadm --clear ; rm -rf ~/.kube

关键提示信息：
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/ 

You can now join any number of the control-plane node running the following command on each as root: 

 [其他master加入集群]
  kubeadm join 192.168.1.160:16443 --token 7t2weq.bjbawausm0jaxury \
        --discovery-token-ca-cert-hash sha256:aeb438bb077768d6626fbc5f2ff61a903bfea24c2eaaa3fde49bace433176384 \
        --control-plane --certificate-key 530a5f56ce32e4ab69b384f41e6165327e23577f4924558b36efb6bb08a883e5 

Please note that the certificate-key gives access to cluster sensitive data, keep it secret!
As a safeguard, uploaded-certs will be deleted in two hours; If necessary, you can use
"kubeadm init phase upload-certs --upload-certs" to reload certs afterward. 

Then you can join any number of worker nodes by running the following on each as root: 

[其他node加入集群]
kubeadm join 192.168.1.160:16443 --token 7t2weq.bjbawausm0jaxury \
        --discovery-token-ca-cert-hash sha256:aeb438bb077768d6626fbc5f2ff61a903bfea24c2eaaa3fde49bace433176384  

#优化
mkdir -p $HOME/.kube
sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
sudo chown $(id -u):$(id -g) $HOME/.kube/config
cat <<EOF >> /root/.bashrc
export KUBECONFIG=/etc/kubernetes/admin.conf
EOF
source /root/.bashrc

4.3 master02 master03 加入master集群

#Token过期后生成新的token：
kubeadm token create --print-join-command

#Master需要生成-certificate-key
root@k8s-master01[15:36:45]:~$ kubeadm init phase upload-certs --upload-certs
[upload-certs] Storing the certificates in Secret "kubeadm-certs" in the "kube-system" Namespace
[upload-certs] Using certificate key:
9b5153fe13fe5a9286eb68fae35311f7357b854a2f8ad925bc7e45b16d2b886e 

#其他master加入集群
kubeadm join 192.168.1.160:16443 --token fgtxr1.bz6dw1tci1kbj977    --discovery-token-ca-cert-hash sha256:06ebf46458a41922ff1f5b3bc49365cf3dd938f1a7e3e4a8c8049b5ec5a3aaa5 \
   --control-plane --certificate-key 9b5153fe13fe5a9286eb68fae35311f7357b854a2f8ad925bc7e45b16d2b886e

4.4 node01 node02 加入node集群

kubeadm join 192.168.1.160:16443 --token 7t2weq.bjbawausm0jaxury --discovery-token-ca-cert-hash sha256:aeb438bb077768d6626fbc5f2ff61a903bfea24c2eaaa3fde49bace433176384

#过程
root@k8s-node01[15:29:45]:~$ kubeadm join 192.168.1.160:16443 --token 7t2weq.bjbawausm0jaxury \
> --discovery-token-ca-cert-hash sha256:aeb438bb077768d6626fbc5f2ff61a903bfea24c2eaaa3fde49bace433176384
[preflight] Running pre-flight checks
[preflight] Reading configuration from the cluster...
[preflight] FYI: You can look at this config file with 'kubectl -n kube-system get cm kubeadm-config -o yaml'
[kubelet-start] Writing kubelet configuration to file "/var/lib/kubelet/config.yaml"
[kubelet-start] Writing kubelet environment file with flags to file "/var/lib/kubelet/kubeadm-flags.env"
[kubelet-start] Starting the kubelet
[kubelet-start] Waiting for the kubelet to perform the TLS Bootstrap... 

This node has joined the cluster:
* Certificate signing request was sent to apiserver and a response was received.
* The Kubelet was informed of the new secure connection details. 

Run 'kubectl get nodes' on the control-plane to see this node join the cluster.

4.5 加入结果概览

root@k8s-master01[16:06:10]:~$ kubectl get nodes
NAME           STATUS     ROLES                  AGE     VERSION
k8s-master01   NotReady   control-plane,master   6m15s   v1.21.0
k8s-master02   NotReady   control-plane,master   5m23s   v1.21.0
k8s-master03   NotReady   control-plane,master   4m21s   v1.21.0
k8s-node01     NotReady   <none>                 11s     v1.21.0
k8s-node02     NotReady   <none>                 0s      v1.21.0

采用初始化安装方式，所有的系统组件均以容器的方式运行并且在kube-system命名空间内，此时可以查看Pod状态：
root@k8s-master01[20:18:57]:~$ kubectl get pod -n kube-system
NAME                                   READY   STATUS    RESTARTS   AGE
coredns-57d4cbf879-8vs6c               0/1     Pending   0          75m
coredns-57d4cbf879-p99nc               0/1     Pending   0          75m
etcd-k8s-master01                      1/1     Running   0          75m
etcd-k8s-master02                      1/1     Running   0          4m45s
etcd-k8s-master03                      1/1     Running   0          4m23s
kube-apiserver-k8s-master01            1/1     Running   0          75m
kube-apiserver-k8s-master02            1/1     Running   0          4m45s
kube-apiserver-k8s-master03            1/1     Running   0          4m10s
kube-controller-manager-k8s-master01   1/1     Running   1          75m
kube-controller-manager-k8s-master02   1/1     Running   0          4m45s
kube-controller-manager-k8s-master03   1/1     Running   0          4m21s
kube-proxy-2zc6p                       1/1     Running   0          4m46s
kube-proxy-djtbn                       1/1     Running   0          3m30s
kube-proxy-g2ddr                       1/1     Running   0          75m
kube-proxy-gf7w8                       1/1     Running   0          3m34s
kube-proxy-mfsbz                       1/1     Running   0          3m59s
kube-scheduler-k8s-master01            1/1     Running   1          75m
kube-scheduler-k8s-master02            1/1     Running   0          4m45s
kube-scheduler-k8s-master03            1/1     Running   0          4m19s 

#出现 coredns Pending状态 重新下载这个包，然后再次查看
docker pull registry.cn-beijing.aliyuncs.com/dotbalo/coredns:1.8.0
docker tag registry.cn-beijing.aliyuncs.com/dotbalo/coredns:1.8.0 registry.cn-hangzhou.aliyuncs.com/google_containers/coredns/coredns:v1.8.0

#此时 coredns已经启动完毕
root@k8s-master01[20:44:59]:~$ kubectl get pod -n kube-system
NAME                                      READY   STATUS    RESTARTS   AGE
calico-kube-controllers-cdd5755b9-tfhp8   1/1     Running   0        7m31s
calico-node-4rsfw                         1/1     Running   0        7m31s
calico-node-cgjjw                         1/1     Running   0        7m31s
calico-node-gw2zz                         1/1     Running   0        7m31s
calico-node-hzjn7                         1/1     Running   0        7m31s
calico-node-sbjx4                         1/1     Running   0        7m31s
coredns-57d4cbf879-8vs6c                  1/1     Running   0         100m
coredns-57d4cbf879-p99nc                  1/1     Running   0         100m
etcd-k8s-master01                         1/1     Running   0         100m
etcd-k8s-master02                         1/1     Running   0          29m
etcd-k8s-master03                         1/1     Running   0          29m
kube-apiserver-k8s-master01               1/1     Running   0         100m
kube-apiserver-k8s-master02               1/1     Running   0          29m
kube-apiserver-k8s-master03               1/1     Running   0          29m
kube-controller-manager-k8s-master01      1/1     Running   1         100m
kube-controller-manager-k8s-master02      1/1     Running   0          29m
kube-controller-manager-k8s-master03      1/1     Running   0          29m
kube-proxy-2zc6p                          1/1     Running   0          29m
kube-proxy-djtbn                          1/1     Running   0          28m
kube-proxy-g2ddr                          1/1     Running   0         100m
kube-proxy-gf7w8                          1/1     Running   0          28m
kube-proxy-mfsbz                          1/1     Running   0          28m
kube-scheduler-k8s-master01               1/1     Running   1         100m
kube-scheduler-k8s-master02               1/1     Running   0          29m
kube-scheduler-k8s-master03               1/1     Running   0          29m

4.6 Master01节点配置环境变量，用于访问Kubernetes集群：

cat <<EOF >> /root/.bashrc
export KUBECONFIG=/etc/kubernetes/admin.conf
EOF
source /root/.bashrc

4.7 安装calico网络组件[master01操作]

/** 以下步骤只在master01执行 **/
cd /root/k8s-ha-install && git checkout manual-installation-v1.21.x && cd calico/

修改calico-etcd.yaml的以下位置:

sed -i 's#etcd_endpoints: "http://<ETCD_IP>:<ETCD_PORT>"#etcd_endpoints: "https://192.168.1.151:2379,https://192.168.1.152:2379,https://192.168.1.153:2379"#g' calico-etcd.yaml
ETCD_CA=`cat /etc/kubernetes/pki/etcd/ca.crt " base64 " tr -d '\n'`
ETCD_CERT=`cat /etc/kubernetes/pki/etcd/server.crt " base64 " tr -d '\n'`
ETCD_KEY=`cat /etc/kubernetes/pki/etcd/server.key " base64 " tr -d '\n'`

#修改网段
sed -i "s@# etcd-key: null@etcd-key: ${ETCD_KEY}@g; s@# etcd-cert: null@etcd-cert: ${ETCD_CERT}@g; s@# etcd-ca: null@etcd-ca: ${ETCD_CA}@g" calico-etcd.yaml

sed -i 's#etcd_ca: ""#etcd_ca: "/calico-secrets/etcd-ca"#g; s#etcd_cert: ""#etcd_cert: "/calico-secrets/etcd-cert"#g; s#etcd_key: "" #etcd_key: "/calico-secrets/etcd-key" #g' calico-etcd.yaml

POD_SUBNET=`cat /etc/kubernetes/manifests/kube-controller-manager.yaml " grep cluster-cidr= " awk -F= '{print $NF}'`

注意下面的这个步骤是把calico-etcd.yaml文件里面的CALICO_IPV4POOL_CIDR下的网段改成自己的Pod网段，也就是把192.168.x.x/16改成自己的集群网段，并打开注释：

所以更改的时候请确保这个步骤的这个网段没有被统一替换掉，如果被替换掉了，还请改回来：

cd /root/k8s-ha-install/calico
sed -i 's@# - name: CALICO_IPV4POOL_CIDR@- name: CALICO_IPV4POOL_CIDR@g; s@#  value: "192.168.0.0/16"@ value: '"${POD_SUBNET}"'@g' calico-etcd.yaml

修改完成后执行：

kubectl apply -f calico-etcd.yaml

查看容器和节点状态:

kubectl get pod -n kube-system

5. Metrics部署

在新版的Kubernetes中系统资源的采集均使用Metrics-server，可以通过Metrics采集节点和Pod的内存、磁盘、CPU和网络的使用率

#将Master01节点的front-proxy-ca.crt复制到所有Node节点
scp -r /etc/kubernetes/pki/front-proxy-ca.crt k8s-node01:/etc/kubernetes/pki/front-proxy-ca.crt
scp -r /etc/kubernetes/pki/front-proxy-ca.crt k8s-node02:/etc/kubernetes/pki/front-proxy-ca.crt
scp -r /etc/kubernetes/pki/front-proxy-ca.crt k8s-master02:/etc/kubernetes/pki/front-proxy-ca.crt
scp -r /etc/kubernetes/pki/front-proxy-ca.crt k8s-master03:/etc/kubernetes/pki/front-proxy-ca.crt

#安装Metrics
cd /root/k8s-ha-install/metrics-server-0.4.x-kubeadm/
kubectl  create -f comp.yaml 

#输出结果：
serviceaccount/metrics-server created
clusterrole.rbac.authorization.k8s.io/system:aggregated-metrics-reader created
clusterrole.rbac.authorization.k8s.io/system:metrics-server created
rolebinding.rbac.authorization.k8s.io/metrics-server-auth-reader created
clusterrolebinding.rbac.authorization.k8s.io/metrics-server:system:auth-delegator created
clusterrolebinding.rbac.authorization.k8s.io/system:metrics-server created
service/metrics-server created
deployment.apps/metrics-server created
apiservice.apiregistration.k8s.io/v1beta1.metrics.k8s.io created

 #查看安装结果：
命令：kubectl get po -n kube-system -l k8s-app=metrics-server
结果：
NAME                             READY   STATUS    RESTARTS   AGE
metrics-server-d6c46b546-4sxb8   1/1     Running   0          114s  

命令：kubectl top po --use-protocol-buffers -A
NAMESPACE     NAME                              CPU(cores)  MEMORY(bytes)
kube-system   calico-kube-controllers                2m       20Mi
kube-system   calico-node-4rsfw                      22m      78Mi
kube-system   calico-node-cgjjw                      26m      75Mi
kube-system   calico-node-gw2zz                      22m      72Mi
kube-system   calico-node-hzjn7                      24m      75Mi
kube-system   calico-node-sbjx4                      23m      70Mi
kube-system   coredns-57d4cbf879-8vs6c                2m      17Mi
kube-system   coredns-57d4cbf879-p99nc                2m      18Mi
kube-system   etcd-k8s-master01                      29m      80Mi
kube-system   etcd-k8s-master02                      25m      79Mi
kube-system   etcd-k8s-master03                      25m      80Mi
kube-system   kube-apiserver-k8s-master01            45m     360Mi
kube-system   kube-apiserver-k8s-master02            31m     352Mi
kube-system   kube-apiserver-k8s-master03            28m     344Mi
kube-system   kube-controller-manager-k8s-master01    2m      27Mi
kube-system   kube-controller-manager-k8s-master02    9m      63Mi
kube-system   kube-controller-manager-k8s-master03    1m      29Mi
kube-system   kube-proxy-2zc6p                        1m      26Mi
kube-system   kube-proxy-djtbn                        1m      25Mi
kube-system   kube-proxy-g2ddr                        1m      24Mi
kube-system   kube-proxy-gf7w8                        1m      26Mi
kube-system   kube-proxy-mfsbz                        1m      23Mi
kube-system   kube-scheduler-k8s-master01             2m      26Mi
kube-system   kube-scheduler-k8s-master02             2m      30Mi
kube-system   kube-scheduler-k8s-master03             2m      27Mi
kube-system   metrics-server-d6c46b546-4sxb8          4m      23Mi

5.1 安装dashboard

#1. 安装老版本
cd /root/k8s-ha-install/dashboard/
kubectl create -f .

#2. 安装最新版：
kubectl apply -f https://raw.githubusercontent.com/kubernetes/dashboard/v2.2.0/aio/deploy/recommended.yaml

#授权：
vim admin.yaml
#--------------------------admin.yaml--------------------------#
apiVersion: v1
kind: ServiceAccount
metadata:
  name: admin-user
  namespace: kube-system
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
  name: admin-user
  annotations:
    rbac.authorization.kubernetes.io/autoupdate: "true"
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: cluster-admin
subjects:
- kind: ServiceAccount
  name: admin-user
  namespace: kube-system
#--------------------------admin.yaml--------------------------#

#执行安装
kubectl apply -f admin.yaml -n kube-system

5.2 登录dashboard

在谷歌浏览器（Chrome）启动文件中加入启动参数，用于解决无法访问Dashboard的问题，参考图1-1：

谷歌浏览器添加参数：
--test-type --ignore-certificate-errors

2.更改dashboard的svc为NodePort：

kubectl edit svc kubernetes-dashboard -n kubernetes-dashboard

spec:
  clusterIP: 10.108.157.21
  clusterIPs:
  - 10.108.157.21
  externalTrafficPolicy: Cluster
  ports:
  - nodePort: 30195
    port: 443
    protocol: TCP
    targetPort: 8443
  selector:
    k8s-app: kubernetes-dashboard
  sessionAffinity: None
  type: ClusterIP     #改为 NodePort 

#修改完成后如下：
spec:
  clusterIP: 10.108.157.21
  clusterIPs:
  - 10.108.157.21
  externalTrafficPolicy: Cluster
  ports:
  - nodePort: 30195
    port: 443
    protocol: TCP
    targetPort: 8443
  selector:
    k8s-app: kubernetes-dashboard
  sessionAffinity: None
  type: NodePort      #已经改为NodePort

修改完成后访问dashboard：
#查看端口号：
kubectl get svc kubernetes-dashboard -n kubernetes-dashboard

通过https协议进行访问

https://192.168.1.151:32234/

#查看token值：
kubectl -n kube-system describe secret $(kubectl -n kube-system get secret | grep admin-user | awk '{print $1}')

#得到 token:
eyJhbGciOiJSUzI1NiIsImtpZCI6IlFkM3BUd0xxVEZ6a0t4Njl2QnVaMWhLNUl4NFlzUkVrQngzbmlQeG4zczgifQ.eyJpc3MiOiJrdWJlcm5ldGVzL3NlcnZpY2VhY2NvdW50Iiwia3ViZXJuZXRlcy5pby9zZXJ2aWNlYWNjb3VudC9uYW1lc3BhY2UiOiJrdWJlLXN5c3RlbSIsImt1YmVybmV0ZXMuaW8vc2VydmljZWFjY291bnQvc2VjcmV0Lm5hbWUiOiJhZG1pbi11c2VyLXRva2VuLXRidjRkIiwia3ViZXJuZXRlcy5pby9zZXJ2aWNlYWNjb3VudC9zZXJ2aWNlLWFjY291bnQubmFtZSI6ImFkbWluLXVzZXIiLCJrdWJlcm5ldGVzLmlvL3NlcnZpY2VhY2NvdW50L3NlcnZpY2UtYWNjb3VudC51aWQiOiI0MzI2NDM1My1iNzY4LTRlNTEtYjljZS0wY2FlMzJlNThmOTgiLCJzdWIiOiJzeXN0ZW06c2VydmljZWFjY291bnQ6a3ViZS1zeXN0ZW06YWRtaW4tdXNlciJ9.jKtz39e-9EBlLhIW571Ms63ywad2z0s2hEa0ZalBRcEDXDKLN7jDejTLrrcyeNY5pRa8AUtbS1ckiYWI7OOlR3PBjD5Tgaz2HEKFw0FEoNMQnU8uLzR5WbUX4obOpzAyB4WYmCS9vK-ud98mmMHOT15Ee2BeaxIWTBL715m-NJcIxxByvsBtogVj7zWJayAVLOspMLps8hWk8XJDXpWEx0J8uU9KUPOey3YMiO5gNlk5TRHcZJOGg_7HV8_55MqKTQ8K9Jhsu5uVieB3kuJdwJdcGCGrMi1UVGx-RgJwGbZqMkXgy55QAp2he_sNFZmThhuxvz7FIclUyyoUZ43V9Q

将token粘贴到web页面上的token输入栏

登录成功界面：

6. 配置修改

将Kube-proxy改为ipvs模式，因为在初始化集群的时候注释了ipvs配置，所以需要自行修改一下：

在master01节点执行

kubectl edit cm kube-proxy -n kube-system
mode： 修改为 mode: ipvs

更新Kube-Proxy的Pod：
kubectl patch daemonset kube-proxy -p "{\"spec\":{\"template\":{\"metadata\":{\"annotations\":{\"date\":\"`date +'%s'`\"}}}}}" -n kube-system

验证Kube-Proxy模式：
root@k8s-master01[14:52:28]:~/k8s-ha-install/dashboard$ curl 127.0.0.1:10249/proxyMode
kubectl edit cm kube-proxy -n kube-system
mode: ipvs

更新Kube-Proxy的Pod：

kubectl patch daemonset kube-proxy -p "{\"spec\":{\"template\":{\"metadata\":{\"annotations\":{\"date\":\"`date +'%s'`\"}}}}}" -n kube-system

验证Kube-Proxy模式：

[root@k8s-master01 1.1.1]# curl 127.0.0.1:10249/proxyMode
ipvs

集群部署完成状态:

root@k8s-master01[21:29:32]:~$ kubectl get nodes
NAME           STATUS   ROLES                  AGE    VERSION
k8s-master01   Ready    control-plane,master   145m   v1.21.0
k8s-master02   Ready    control-plane,master   73m    v1.21.0
k8s-master03   Ready    control-plane,master   73m    v1.21.0
k8s-node01     Ready    <none>                 72m    v1.21.0
k8s-node02     Ready    <none>                 72m    v1.21.0

root@k8s-master01[21:29:33]:~$ cat /etc/hosts
127.0.0.1   localhost localhost.localdomain localhost4 localhost4.localdomain4
::1         localhost localhost.localdomain localhost6 localhost6.localdomain6
192.168.1.151 k8s-master01
192.168.1.152 k8s-master02
192.168.1.153 k8s-master03
192.168.1.160 k8s-master-lb
192.168.1.154 k8s-node01
192.168.1.155 k8s-node02

7. 高可用测试

k8s-master01是vip地址，停止eth0后vip消失

停止后，vip地址在master02上漂移成功