第一章 1.1.1节 Kubeadm安装K8S高可用集群
阅读原文时间:2023年07月09日阅读:1

1.1 安装前必读

请不要使用带中文的服务器和克隆的虚拟机。

生产环境建议使用二进制的方式安装。

文档中的IP地址要更换成自己的IP地址,要谨记!!!

1.2 基本环境配置

kubeadm安装方式自1.14版本以后,安装方法几乎没有任何变化,此文档可以尝试安装最新的K8S集群,centos采用的是7.x版本。

K8S官网:

https://kubernetes.io/docs/setup/

最新版高可用安装:

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

主机名

IP地址

说明

k8s-master01

10.3.50.11

master节点1

k8s-master02

10.3.50.12

master节点2

k8s-master03

10.3.50.13

master节点3

k8s-master-lb

10.3.50.100

keepalived虚拟IP

k8s-node01

10.3.50.14

work节点

k8s-node02

10.3.50.15

work节点

配置信息

备注

系统版本

CentOS 7.9

Docker版本

20.10.x

Pod网段

10.16.0.0/12

Service网段

10.244.0.0/16

注意:宿主机网段、k8s Service网段、Pod网段不能重复!!!

VIP(虚拟IP)不要和公司内网IP重复,首先去ping一下,不通才可用。VIP需要和你的主机在同一个局域网内(不是直接用上述IP,要和本主机网段相同)!

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。不需要再搭建keepalived和haproxy!

所有节点配置hosts,修改/etc/hosts如下:

注意用自己本机的IP地址!!!

[root@k8s-master01 ~]# vim /etc/hosts
10.3.50.11 k8s-master01
10.3.50.12 k8s-master02
10.3.50.13 k8s-master03
10.3.50.100 k8s-master-lb      # 如果不是高可用集群,该IP为master01的IP!
10.3.50.14 k8s-node01
10.3.50.15 k8s-node02

CentOS 7安装yum源如下:

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 < /etc/yum.repos.d/kubernetes.repo
[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

sed -i -e '/mirrors.cloud.aliyuncs.com/d' -e '/mirrors.aliyuncs.com/d' /etc/yum.repos.d/CentOS-Base.repo

必备工具安装

yum install wget jq psmisc vim net-tools telnet yum-utils device-mapper-persistent-data lvm2 git -y

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      # 公有云不要关闭

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
yum install ntpdate -y

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
crntab -e

加入到crontab

*/5 * * * * /usr/sbin/ntpdate time2.aliyun.com

所有节点配置limit:

ulimit -SHn 65535

vim /etc/security/limits.conf

末尾添加如下内容

* soft nofile 65536
* hard nofile 131072
* soft nproc 65535
* hard nproc 655350
* soft memlock unlimited
* hard memlock unlimited

master01节点免密钥登陆其他节点,安装过程中生成配置文件和证书均在master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:

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

下载安装所有的源码文件:

cd /root/
git clone https://github.com/dotbalo/k8s-ha-install.git    
git clone https://gitee.com/dukuan/k8s-ha-install.git      # 如果上面的无法下载就使用这个

如果无法下载就下载:

https://gitee.com/dukuan/k8s-ha-install.git

所有节点升级系统并重启,此处没有升级内核。

yum update -y --exclude=kernel* && reboot      # CentOS 7需要升级,CentOS 8可以按需升级系统

1.3 内核配置

CentOS 7需要升级内核至4.18+,本地升级的版本为4.19。

在master01节点下载内核!

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 ~]# 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-master02 ~]# uname -a
Linux k8s-master02 4.19.12-1.el7.elrepo.x86_64 #1 SMP Fri Dec 21 11:06:36 EST 2018 x86_64 x86_64 x86_64 GNU/Linux

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
vim /etc/modules-load.d/ipvs.conf

加入以下内容

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

然后执行systemctl enable --now systemd-modules-load.service即可

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 < /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
net.ipv4.conf.all.route_localnet = 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

1.4 k8s组件和Runtime安装

如果安装的版本低于1.24,选择Docker和Containerd均可,高于1.24选择Containerd作为Runtime。

注意:Runtime安装选择两个小节的其中一个小节即可。

所有节点安装docker-ce-20.10:

yum install docker-ce-20.10.* docker-ce-cli-20.10.* -y

可以无需启动Docker,只需要配置和启动Containerd即可。

首先配置Containerd所需的模块(所有节点):

cat <<EOF | sudo tee /etc/modules-load.d/containerd.conf
overlay
br_netfilter
EOF

所有节点加载模块:

modprobe -- overlay
modprobe -- br_netfilter

所有节点,配置Containerd所需的内核:

cat <<EOF | sudo tee /etc/sysctl.d/99-kubernetes-cri.conf
net.bridge.bridge-nf-call-iptables = 1
net.ipv4.ip_forward = 1
net.bridge.bridge-nf-call-ip6tables = 1
EOF

所有节点加载内核:

sysctl --system

所有节点配置Containerd的配置文件:

mkdir -p /etc/containerd
containerd config default | tee /etc/containerd/config.toml

所有节点将Containerd的Ggroup改为Systemd:

vim /etc/containerd/config.toml

找到containerd.runtimes.runc.options,添加SystemdCgroup = true(如果已存在直接修改,否则会报错),如下图:

所有节点将sandbox_image的Pause镜像改成符合自己版本的地址registry.cn-hangzhou.aliyuncs.com/google_containers/pause:3.6:

所有节点启动Containerd,并配置开机自启动:

systemctl daemon-reload
systemctl enable --now containerd

所有节点配置crictl客户端连接的运行时位置:

cat > /etc/crictl.yaml <<EOF
runtime-endpoint: unix:///run/containerd/containerd.sock
image-endpoint: unix:///run/containerd/containerd.sock
timeout: 10
debug: false
EOF

如果选择Docker作为Runtime,安装步骤较Containerd较为简单,只需要安装并启动即可。

所有节点安装docker-ce 20.10:

yum install docker-ce-20.10.* docker-ce-cli-20.10.* -y

由于新版kubelet建议使用systemd,所以把Docker的CgroupDriver也改成systemd:

mkdir /etc/docker
cat > /etc/docker/daemon.json <<EOF
{
"exec-opts": ["native.cgroupdriver=systemd"]
}
EOF

所有节点设置开机自启动Docker:

systemctl daemon-reload && systemctl enable --now docker

1.5 安装Kubernetes组件

首先在master01节点查看最新的Kubernetes版本是多少:

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

所有节点安装1.23最新版本kubeadm、kubelet和kubectl:

yum install kubeadm-1.23* kubelet-1.23* kubectl-1.23* -y

如果选择的是Containerd作为Runtime的,需要更改Kubelet的配置使用Containerd作为Runtime:

cat >/etc/sysconfig/kubelet<<EOF
KUBELET_KUBEADM_ARGS="--container-runtime=remote --runtime-request-timeout=15m --container-runtime-endpoint=unix:///run/containerd/containerd.sock"
EOF

注意:如果不是采用Containerd作为Runtime的,请不要执行上述命令!!!

所有节点设置kubelet开机自启动(由于还未初始化,没有kubelet的配置文件,此时kubelet无法启动,无需管理):

systemctl daemon-reload
systemctl enable --now kubelet

此时kubelet是起不来的,日志会有报错不影响!

1.6 高可用组件安装

(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,kubelet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:

yum install keepalived haproxy -y

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):

[root@k8s-master01 etc]# mkdir /etc/haproxy
[root@k8s-master01 etc]# vim /etc/haproxy/haproxy.cfg
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 10.3.50.11:6443 check
server k8s-master02 10.103.236.202:6443 check
server k8s-master03 10.103.236.203:6443 check

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)

master01节点的配置:

[root@k8s-master01 etc]# mkdir /etc/keepalived

[root@k8s-master01 ~]# vim /etc/keepalived/keepalived.conf
! 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 ens33
mcast_src_ip 10.3.50.11
virtual_router_id 51
priority 101
advert_int 2
authentication {
auth_type PASS
auth_pass K8SHA_KA_AUTH
}
virtual_ipaddress {
10.3.50.100
}
track_script {
chk_apiserver
}
}

master02节点的配置:

! 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 ens33
mcast_src_ip 10.103.236.202
virtual_router_id 51
priority 100
advert_int 2
authentication {
auth_type PASS
auth_pass K8SHA_KA_AUTH
}
virtual_ipaddress {
10.3.50.100
}
track_script {
chk_apiserver
}
}

master03节点的配置:

! 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 ens33
mcast_src_ip 10.103.236.203
virtual_router_id 51
priority 100
advert_int 2
authentication {
auth_type PASS
auth_pass K8SHA_KA_AUTH
}
virtual_ipaddress {
10.3.50.100
}
track_script {
chk_apiserver
}
}

所有master节点配置keepalived健康检查文件:

[root@k8s-master01 keepalived]# cat /etc/keepalived/check_apiserver.sh
#!/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

chmod +x /etc/keepalived/check_apiserver.sh

启动haproxy和keepalived

[root@k8s-master01 keepalived]# systemctl daemon-reload
[root@k8s-master01 keepalived]# systemctl enable --now haproxy
[root@k8s-master01 keepalived]# systemctl enable --now keepalived

重要:如果安装了keepalived和haproxy,需要测试keepalived是否是正常的

测试VIP
[root@k8s-master01 ~]# ping 10.3.50.100 -c 4
PING 10.3.50.100 (10.3.50.100) 56(84) bytes of data.
64 bytes from 10.3.50.100: icmp_seq=1 ttl=64 time=0.464 ms
64 bytes from 10.3.50.100: icmp_seq=2 ttl=64 time=0.063 ms
64 bytes from 10.3.50.100: icmp_seq=3 ttl=64 time=0.062 ms
64 bytes from 10.3.50.100: icmp_seq=4 ttl=64 time=0.063 ms

--- 10.3.50.100 ping statistics ---
4 packets transmitted, 4 received, 0% packet loss, time 3106ms
rtt min/avg/max/mdev = 0.062/0.163/0.464/0.173 ms
[root@k8s-master01 ~]# telnet 10.3.50.100 16443
Trying 10.3.50.100…
Connected to 10.3.50.100.
Escape character is '^]'.
Connection closed by foreign host.

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

1.7 集群初始化

官方初始化文档:

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

以下操作只在master01节点执行

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,10.3.50.100:16443改为master01的地址,16443改为apiserver的端口,默认是6443,注意更改kubernetesVersion的值和自己服务器kubeadm的版本一致:kubeadm version)

以下文件内容,宿主机网段、podSubnet网段、serviceSubnet网段不能重复。

以下操作在master01:

vim 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: 10.3.50.11
      bindPort: 6443
      nodeRegistration:
      # criSocket: /var/run/dockershim.sock      # 如果是Docker作为Runtime配置此项
      criSocket: /run/containerd/containerd.sock      # 如果是Containerd作为Runtime配置此项
      name: k8s-master01
      taints:
    • effect: NoSchedule

key: node-role.kubernetes.io/master

apiServer:
certSANs:

  • 10.3.50.100
    timeoutForControlPlane: 4m0s
    apiVersion: kubeadm.k8s.io/v1beta2
    certificatesDir: /etc/kubernetes/pki
    clusterName: kubernetes
    controlPlaneEndpoint: 10.3.50.100:16443
    controllerManager: {}
    dns:
    type: CoreDNS
    etcd:
    local:
    dataDir: /var/lib/etcd
    imageRepository: registry.cn-hangzhou.aliyuncs.com/google_containers
    kind: ClusterConfiguration
    kubernetesVersion: v1.23.0      # 更改此处的版本号和kubeadm version一致
    networking:
    dnsDomain: cluster.local
    podSubnet: 10.16.0.0/12
    serviceSubnet: 10.244.0.0/16
    scheduler: {}

更新kubeadm文件

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

for i in k8s-master02 k8s-master03; do scp new.yaml $i:/root/; done

之前所有master节点提前下载镜像,可以节省初始化时间(其他节点不需要更改任何配置,包括IP地址也不需要更改);

kubeadm config images pull --config /root/new.yaml

所有节点设置开机自启动kubelet

systemctl enable --now kubelet      #(如果启动失败无需管理,初始化成功以后即可启动)

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:

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(没有失败不要执行):

kubeadm reset -f ; ipvsadm --clear ; rm -rf ~/.kube

初始化成功以后,会产生Token值,用于其他节点加入时使用,因此要记录下初始化成功生成的Token值(令牌值):

Your Kubernetes control-plane has initialized successfully!

To start using your cluster, you need to run the following as a regular user:

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

Alternatively, if you are the root user, you can run:

export KUBECONFIG=/etc/kubernetes/admin.conf

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:

kubeadm join 10.3.50.100:16443 --token 7t2weq.bjbawausm0jaxury \
--discovery-token-ca-cert-hash sha256:df72788de04bbc2e8fca70becb8a9e8503a962b5d7cd9b1842a0c39930d08c94 \
--control-plane --certificate-key c595f7f4a7a3beb0d5bdb75d9e4eff0a60b977447e76c1d6885e82c3aa43c94c

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:

kubeadm join 10.3.50.100:16443 --token 7t2weq.bjbawausm0jaxury \
--discovery-token-ca-cert-hash sha256:df72788de04bbc2e8fca70becb8a9e8503a962b5d7cd9b1842a0c39930d08c94

master01节点配置环境变量,用于访问Kubernetes集群:

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

查看节点状态:

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命令空间内,此时可以查看Pod状态:

1.8 高可用Master

注意:以下步骤是上述init命令产生的Token过期了才需要执行以下步骤,如果没有过期不需要执行,直接join即可

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

Master需要生成--certificate-key
kubeadm init phase upload-certs --upload-certs

Token没有过期直接执行Join就行了

其他master加入集群,master02和master03分别执行

kubeadm join 10.3.50.100:16443 --token 7t2weq.bjbawausm0jaxury \
--discovery-token-ca-cert-hash sha256:df72788de04bbc2e8fca70becb8a9e8503a962b5d7cd9b1842a0c39930d08c94 \
--control-plane --certificate-key c595f7f4a7a3beb0d5bdb75d9e4eff0a60b977447e76c1d6885e82c3aa43c94c

查看当前状态:

1.9 Node节点的配置

Node节点上主要部署公司的一些业务应用,生产环境中不建议master节点部署系统组件之外的其他Pod,测试环境可以允许master节点部署Pod以节省系统资源。

kubeadm join 10.3.50.100:16443 --token 7t2weq.bjbawausm0jaxury \
--discovery-token-ca-cert-hash sha256:df72788de04bbc2e8fca70becb8a9e8503a962b5d7cd9b1842a0c39930d08c94

所有节点初始化完成后,查看集群状态

2.0 Calico组件的安装

以下步骤只在master01执行

cd /root/k8s-ha-install && git checkout manual-installation-v1.23.x && cd calico/

修改Pod网段:

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

sed -i "s#POD_CIDR#${POD_SUBNET}#g" calico.yaml
kubectl apply -f calico.yaml

查看容器和节点状态:

2.1 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 /etc/kubernetes/pki/front-proxy-ca.crt k8s-node01:/etc/kubernetes/pki/front-proxy-ca.crt
scp /etc/kubernetes/pki/front-proxy-ca.crt k8s-node(其他节点自行拷贝):/etc/kubernetes/pki/front-proxy-ca.crt

安装metrics server

cd /root/k8s-ha-install/kubeadm-metrics-server

kubectl create -f comp.yaml

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

查看状态

kubectl get po -n kube-system -l k8s-app=metrics-server

变成1/1     Running后

# kubectl top node
NAME CPU(cores) CPU% MEMORY(bytes) MEMORY%
k8s-master01 153m 3% 1701Mi 44%
k8s-master02 125m 3% 1693Mi 44%
k8s-master03 129m 3% 1590Mi 41%
k8s-node01 73m 1% 989Mi 25%
k8s-node02 64m 1% 950Mi 24%

kubectl top po -A

NAMESPACE NAME CPU(cores) MEMORY(bytes)
kube-system calico-kube-controllers-66686fdb54-74xkg 2m 17Mi
kube-system calico-node-6gqpb 21m 85Mi
kube-system calico-node-bmvjt 29m 76Mi
kube-system calico-node-hdp9c 15m 82Mi
kube-system calico-node-wwrfv 23m 86Mi
kube-system calico-node-zzv88 22m 84Mi
kube-system calico-typha-67c6dc57d6-hj6l4 2m 23Mi
kube-system calico-typha-67c6dc57d6-jm855 2m 22Mi
kube-system coredns-7d89d9b6b8-sr6mf 1m 16Mi
kube-system coredns-7d89d9b6b8-xqwjk 1m 16Mi
kube-system etcd-k8s-master01 24m 96Mi
kube-system etcd-k8s-master02 20m 91Mi
kube-system etcd-k8s-master03 21m 92Mi
kube-system kube-apiserver-k8s-master01 41m 502Mi
kube-system kube-apiserver-k8s-master02 35m 476Mi
kube-system kube-apiserver-k8s-master03 71m 480Mi
kube-system kube-controller-manager-k8s-master01 15m 65Mi
kube-system kube-controller-manager-k8s-master02 1m 26Mi
kube-system kube-controller-manager-k8s-master03 2m 27Mi
kube-system kube-proxy-8lt45 1m 18Mi
kube-system kube-proxy-d6jfh 1m 18Mi
kube-system kube-proxy-hfnvz 1m 19Mi
kube-system kube-proxy-nsms8 1m 18Mi
kube-system kube-proxy-xmlhq 3m 21Mi
kube-system kube-scheduler-k8s-master01 2m 26Mi
kube-system kube-scheduler-k8s-master02 2m 24Mi
kube-system kube-scheduler-k8s-master03 2m 24Mi
kube-system metrics-server-d54b585c4-4dqpf 46m 16Mi

2.2 Dashboard部署

Dashboard用于展示集群中的各类资源,同时也可以通过Dashboard实时查看Pod的日志和在容器中执行一些命令等。

cd /root/k8s-ha-install/dashboard/

[root@k8s-master01 dashboard]# kubectl create -f .
serviceaccount/admin-user created
clusterrolebinding.rbac.authorization.k8s.io/admin-user created
namespace/kubernetes-dashboard created
serviceaccount/kubernetes-dashboard created
service/kubernetes-dashboard created
secret/kubernetes-dashboard-certs created
secret/kubernetes-dashboard-csrf created
secret/kubernetes-dashboard-key-holder created
configmap/kubernetes-dashboard-settings created
role.rbac.authorization.k8s.io/kubernetes-dashboard created
clusterrole.rbac.authorization.k8s.io/kubernetes-dashboard created
rolebinding.rbac.authorization.k8s.io/kubernetes-dashboard created
clusterrolebinding.rbac.authorization.k8s.io/kubernetes-dashboard created
deployment.apps/kubernetes-dashboard created
service/dashboard-metrics-scraper created
deployment.apps/dashboard-metrics-scraper created

官方GitHub地址:

https://github.com/kubernetes/dashboard

可以在官方dashboard查看到最新版dashboard

kubectl apply -f https://raw.githubusercontent.com/kubernetes/dashboard/v2.0.3/aio/deploy/recommended.yaml

2.0.3以具体版本号为准

vim 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

kubectl apply -f admin.yaml -n kube-system

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:

--test-type --ignore-certificate-errors

更改dashboard的svc为NodePort:

kubectl edit svc kubernetes-dashboard -n kubernetes-dashboard

将ChusterIP更改为NodePort(如果已经为NodePort忽略此步骤):

查看端口号:

kubectl get svc kubernetes-dashboard -n kubernetes-dashboard

根据自己的实例端口号,通过任意安装了kube-proxy的宿主机的IP+端口即可访问到dashboard:

访问Dashboard:

https://10.3.50.11:18282(请更改18282为自己的端口)选择登陆方式为令牌(即Token方式),参考图1-2

查看Token值:

[root@k8s-master01 1.1.1]# kubectl -n kube-system describe secret $(kubectl -n kube-system get secret | grep admin-user | awk '{print $1}')
Name: admin-user-token-r4vcp
Namespace: kube-system
Labels:
Annotations: kubernetes.io/service-account.name: admin-user
kubernetes.io/service-account.uid: 2112796c-1c9e-11e9-91ab-000c298bf023

Type: kubernetes.io/service-account-token

Data

ca.crt: 1025 bytes
namespace: 11 bytes
token: eyJhbGciOiJSUzI1NiIsImtpZCI6IiJ9.eyJpc3MiOiJrdWJlcm5ldGVzL3NlcnZpY2VhY2NvdW50Iiwia3ViZXJuZXRlcy5pby9zZXJ2aWNlYWNjb3VudC9uYW1lc3BhY2UiOiJrdWJlLXN5c3RlbSIsImt1YmVybmV0ZXMuaW8vc2VydmljZWFjY291bnQvc2VjcmV0Lm5hbWUiOiJhZG1pbi11c2VyLXRva2VuLXI0dmNwIiwia3ViZXJuZXRlcy5pby9zZXJ2aWNlYWNjb3VudC9zZXJ2aWNlLWFjY291bnQubmFtZSI6ImFkbWluLXVzZXIiLCJrdWJlcm5ldGVzLmlvL3NlcnZpY2VhY2NvdW50L3NlcnZpY2UtYWNjb3VudC51aWQiOiIyMTEyNzk2Yy0xYzllLTExZTktOTFhYi0wMDBjMjk4YmYwMjMiLCJzdWIiOiJzeXN0ZW06c2VydmljZWFjY291bnQ6a3ViZS1zeXN0ZW06YWRtaW4tdXNlciJ9.bWYmwgRb-90ydQmyjkbjJjFt8CdO8u6zxVZh-19rdlL_T-n35nKyQIN7hCtNAt46u6gfJ5XXefC9HsGNBHtvo_Ve6oF7EXhU772aLAbXWkU1xOwQTQynixaypbRIas_kiO2MHHxXfeeL_yYZRrgtatsDBxcBRg-nUQv4TahzaGSyK42E_4YGpLa3X3Jc4t1z0SQXge7lrwlj8ysmqgO4ndlFjwPfvg0eoYqu9Qsc5Q7tazzFf9mVKMmcS1ppPutdyqNYWL62P1prw_wclP0TezW1CsypjWSVT4AuJU8YmH8nTNR1EXn8mJURLSjINv6YbZpnhBIPgUGk1JYVLcn47w

将Token值输入到令牌后,单机登陆即可访问Dashboard,参考图1-3:

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: 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

2.3 【必看】注意事项

注意:kubeadm安装的集群,证书有效期默认是一年。master节点的kube-apiserver、kube-scheduler、kube-controller-manager、etcd都是以容器运行的。可以通过kubectl get po -n kube-system查看。

启动和二进制不同的是,kubelet的配置文件在/etc/sysconfig/kubelet和/var/lib/kubelet/config.yaml,修改后需要重启kubelet进程。

其他组件的配置文件在/etc/kubernetes/manifests目录下,比如kube-apiserver.yaml,该yaml文件更改后,kubelet会自动刷新配置,也就是会重启Pod。不能再次创建该文件kube-proxy的配置在kube-system明明空间下的configmap中,可以通过

kubectl edit cm kube-proxy -n kube-system

进行更改,更改完成后,可以通过patch重启kube-proxy

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

kubeadm安装后,master节点默认不允许部署Pod,可以通过以下方式打开:

查看Taints:

[root@k8s-master01 ~]# kubectl describe node -l node-role.kubernetes.io/master= | grep Taints
Taints: node-role.kubernetes.io/master:NoSchedule
Taints: node-role.kubernetes.io/master:NoSchedule
Taints: node-role.kubernetes.io/master:NoSchedule

删除Taint:

[root@k8s-master01 ~]# kubectl taint node -l node-role.kubernetes.io/master node-role.kubernetes.io/master:NoSchedule-
node/k8s-master01 untainted
node/k8s-master02 untainted
node/k8s-master03 untainted
[root@k8s-master01 ~]# kubectl describe node -l node-role.kubernetes.io/master= | grep Taints
Taints:
Taints:
Taints: