k8s1.20.1 集群安装

1,204 阅读10分钟

1 环境准备

1. 1 机器环境

节点CPU核数必须是 :>= 2核 /内存要求必须是:>=2G ,否则k8s无法启动

DNS网络: 最好设置为 本地网络连通的DNS,否则网络不通,无法下载一些镜像

linux内核: linux内核必须是 4 版本以上,因此必须把linux核心进行升级

节点hostname作用IP
kmastermaster192.168.8.121
knode1node1192.168.8.122
knode2node2192.168.8.123

1.2 hostname

[root@base1 ~]# hostnamectl set-hostname kmaster --static
[root@base2 ~]# hostnamectl set-hostname knode1 --static
[root@base3 ~]# hostnamectl set-hostname knode2 --static

1.3 网络设置

[root@base1 ~]# vi /etc/sysconfig/network-scripts/ifcfg-ens33
BOOTPROTO="static" #dhcp改为static 
ONBOOT="yes" #开机启用本配置
IPADDR=192.168.8.121 #静态IP 192.168.8.122/192.168.8.123
GATEWAY=192.168.8.2 #默认网关
NETMASK=255.255.255.0 #子网掩码
DNS1=114.114.114.114 #DNS 配置
DNS2=8.8.8.8 #DNS 配置

$# reboot

1.4 查看主机名

hostname

1.5 配置IP host映射关系

vi /etc/hosts
192.168.8.121 kmaster
192.168.8.122 knode1
192.168.8.123 knode2

1.6 安装依赖环境,注意:每一台机器都需要安装此依赖环境

yum install -y conntrack ntpdate ntp ipvsadm ipset jq iptables curl sysstatlibseccomp wget vim net-tools git iproute lrzsz bash-completion tree bridge-utils unzip bind-utils gcc

1.7 安装iptables,启动iptables,设置开机自启,清空iptables规则,保存当前规则到默认规则

# 关闭防火墙
systemctl stop firewalld && systemctl disable firewalld
# 置空iptables
yum -y install iptables-services && systemctl start iptables && systemctl enable iptables && iptables -F && service iptables save

1.8 关闭selinux

# 闭swap分区【虚拟内存】并且永久关闭虚拟内存
swapoff -a && sed -i '/ swap / s/^\(.*\)$/#\1/g' /etc/fstab
# 关闭selinux
setenforce 0 && sed -i 's/^SELINUX=.*/SELINUX=disabled/' /etc/selinux/config

1.9 升级Linux内核为4.44版本

rpm -Uvh http://www.elrepo.org/elrepo-release-7.0-4.el7.elrepo.noarch.rpm
#安装内核
yum --enablerepo=elrepo-kernel install -y kernel-lt
#设置开机从新内核启动
grub2-set-default 'CentOS Linux (4.4.248-1.el7.elrepo.x86_64) 7 (Core)'
4.4.248-1.el7.elrepo.x86_64

reboot
#注意:设置完内核后,需要重启服务器才会生效。
#查询内核
uname -r

2 安装k8s

2.1 对于k8s,调整内核参数 kubernetes.conf

cat > kubernetes.conf <<EOF
net.bridge.bridge-nf-call-iptables=1
net.bridge.bridge-nf-call-ip6tables=1
net.ipv4.ip_forward=1
net.ipv4.tcp_tw_recycle=0
vm.swappiness=0
vm.overcommit_memory=1
vm.panic_on_oom=0
fs.inotify.max_user_instances=8192
fs.inotify.max_user_watches=1048576
fs.file-max=52706963
fs.nr_open=52706963
net.ipv6.conf.all.disable_ipv6=1
net.netfilter.nf_conntrack_max=2310720
EOF
#将优化内核文件拷贝到/etc/sysctl.d/文件夹下,这样优化文件开机的时候能够被调用
cp kubernetes.conf /etc/sysctl.d/kubernetes.conf
#手动刷新,让优化文件立即生效
sysctl -p /etc/sysctl.d/kubernetes.conf
sysctl: cannot stat /proc/sys/net/netfilter/nf_conntrack_max: No such file or directory

错误解决:

lsmod |grep conntrack
modprobe ip_conntrack
lsmod |grep conntrack
nf_conntrack_ipv4      20480  0
nf_defrag_ipv4         16384  1 nf_conntrack_ipv4
nf_conntrack          114688  1 nf_conntrack_ipv4

sysctl -p /etc/sysctl.d/kubernetes.conf
net.bridge.bridge-nf-call-iptables = 1
net.bridge.bridge-nf-call-ip6tables = 1
net.ipv4.ip_forward = 1
net.ipv4.tcp_tw_recycle = 0
vm.swappiness = 0
vm.overcommit_memory = 1
vm.panic_on_oom = 0
fs.inotify.max_user_instances = 8192
fs.inotify.max_user_watches = 1048576
fs.file-max = 52706963
fs.nr_open = 52706963
net.ipv6.conf.all.disable_ipv6 = 1
net.netfilter.nf_conntrack_max = 2310720

2.2 调整系统临时区

#设置系统时区为中国/上海
timedatectl set-timezone Asia/Tokyo
#将当前的UTC 时间写入硬件时钟
timedatectl set-local-rtc 0
#重启依赖于系统时间的服务
systemctl restart rsyslog
systemctl restart crond

2.3 关闭系统不需要的服务

systemctl stop postfix && systemctl disable postfix

2.4 设置日志保存方式

2.4.1 创建保存日志的目录

mkdir /var/log/journal

2.4.2 创建配置文件存放目录

mkdir /etc/systemd/journald.conf.d

2.4.3 创建配置文件

cat > /etc/systemd/journald.conf.d/99-prophet.conf <<EOF
[Journal]
Storage=persistent
Compress=yes
SyncIntervalSec=5m
RateLimitInterval=30s
RateLimitBurst=1000
SystemMaxUse=10G
SystemMaxFileSize=200M
MaxRetentionSec=2week
ForwardToSyslog=no
EOF

2.4.4 重启systemd journald 的配置

systemctl restart systemd-journald

2.4.5 打开文件数调整(可忽略,不执行)

echo "* soft nofile 65536" >> /etc/security/limits.conf
echo "* hard nofile 65536" >> /etc/security/limits.conf

2.4.6 kube-proxy 开启 ipvs 前置条件

modprobe br_netfilter
cat > /etc/sysconfig/modules/ipvs.modules <<EOF
#!/bin/bash
modprobe -- ip_vs
modprobe -- ip_vs_rr
modprobe -- ip_vs_wrr
modprobe -- ip_vs_sh
modprobe -- nf_conntrack_ipv4
EOF
#使用lsmod命令查看这些文件是否被引导
chmod 755 /etc/sysconfig/modules/ipvs.modules && bash /etc/sysconfig/modules/ipvs.modules && lsmod | grep -e ip_vs -e nf_conntrack_ipv4
ip_vs_sh               16384  0
ip_vs_wrr              16384  0
ip_vs_rr               16384  0
ip_vs                 147456  6 ip_vs_rr,ip_vs_sh,ip_vs_wrr
nf_conntrack_ipv4      20480  0
nf_defrag_ipv4         16384  1 nf_conntrack_ipv4
nf_conntrack          114688  2 ip_vs,nf_conntrack_ipv4
libcrc32c              16384  2 xfs,ip_vs

3 docker部署

3.1 安装docker

yum install -y yum-utils device-mapper-persistent-data lvm2

#紧接着配置一个稳定的仓库、仓库配置会保存到/etc/yum.repos.d/docker-ce.repo文件中
yum-config-manager --add-repo https://download.docker.com/linux/centos/docker-ce.repo
#更新Yum安装的相关Docker软件包&安装Docker CE
yum update -y && yum install docker-ce

3.2 设置docker daemon文件

#创建/etc/docker目录
mkdir /etc/docker
#更新daemon.json文件
cat > /etc/docker/daemon.json <<EOF
{"exec-opts":["native.cgroupdriver=systemd"],"log-driver":"json-file","log-opts":{"max-size":"100m"}}
EOF
#注意:一定注意编码问题,出现错误---查看命令:journalctl -amu docker 即可发现错误
#创建,存储docker配置文件
mkdir -p /etc/systemd/system/docker.service.d

3.3 重启docker服务

systemctl daemon-reload && systemctl restart docker && systemctl enable docker

4 kubeadm[一键安装k8s]

4.1 yum仓库镜像

国内

cat <<EOF > /etc/yum.repos.d/kubernetes.repo
[kubernetes]
name=Kubernetes
baseurl=http://mirrors.aliyun.com/kubernetes/yum/repos/kubernetes-el7-x86_64
enabled=1
gpgcheck=0
repo_gpgcheck=0
gpgkey=http://mirrors.aliyun.com/kubernetes/yum/doc/yum-key.gpg
       http://mirrors.aliyun.com/kubernetes/yum/doc/rpm-package-key.gpg
EOF

官网

cat <<EOF > /etc/yum.repos.d/kubernetes.repo
[kubernetes]
name=Kubernetes
baseurl=https://packages.cloud.google.com/yum/repos/kubernetes-el7-x86_64
enabled=1
gpgcheck=1
repo_gpgcheck=1
gpgkey=https://packages.cloud.google.com/yum/doc/yum-key.gpg https://packages.cloud.google.com/yum/doc/rpm-package-key.gpg
EOF

4.2 安装kubeadm 、kubelet、kubectl(1.20.1)

yum install -y kubelet kubeadm kubectl --disableexcludes=kubernetes
#启动 kubelet
systemctl enable kubelet && systemctl start kubelet

5 准备k8s镜像

5.1 在线拉取镜像

生成默认kubeadm.conf文件

kubeadm config print init-defaults > kubeadm.conf

编辑kubeadm.conf,将Kubernetes版本修改为v1.20.1

下载镜像

kubeadm config images pull --config kubeadm.conf
[config/images] Pulled k8s.gcr.io/kube-apiserver:v1.20.1
[config/images] Pulled k8s.gcr.io/kube-controller-manager:v1.20.1
[config/images] Pulled k8s.gcr.io/kube-scheduler:v1.20.1
[config/images] Pulled k8s.gcr.io/kube-proxy:v1.20.1
[config/images] Pulled k8s.gcr.io/pause:3.2
[config/images] Pulled k8s.gcr.io/etcd:3.4.13-0
[config/images] Pulled k8s.gcr.io/coredns:1.7.0

docker images
k8s.gcr.io/kube-proxy                v1.20.1    e3f6fcd87756   11 days ago     118MB
k8s.gcr.io/kube-apiserver            v1.20.1    75c7f7112080   11 days ago     122MB
k8s.gcr.io/kube-controller-manager   v1.20.1    2893d78e47dc   11 days ago     116MB
k8s.gcr.io/kube-scheduler            v1.20.1    4aa0b4397bbb   11 days ago     46.4MB
k8s.gcr.io/etcd                      3.4.13-0   0369cf4303ff   4 months ago    253MB
k8s.gcr.io/coredns                   1.7.0      bfe3a36ebd25   6 months ago    45.2MB
k8s.gcr.io/pause                     3.2        80d28bedfe5d   10 months ago   683kB

保存镜像

mkdir kubeadm-basic.images
cd kubeadm-basic.images
docker save k8s.gcr.io/kube-apiserver:v1.20.1 > apiserver.tar
docker save k8s.gcr.io/coredns:1.7.0 > coredns.tar
docker save k8s.gcr.io/etcd:3.4.13-0 > etcd.tar
docker save k8s.gcr.io/kube-controller-manager:v1.20.1 > kubec-con-man.tar
docker save k8s.gcr.io/pause:3.2 > pause.tar
docker save k8s.gcr.io/kube-proxy:v1.20.1 > proxy.tar
docker save k8s.gcr.io/kube-scheduler:v1.20.1 > scheduler.tar

cd ..
tar zcvf kubeadm-basic.images.tar.gz kubeadm-basic.images

5.2 离线镜像

链接:pan.baidu.com/s/1UAF_-_sG…
提取码:548z

上传镜像压缩包kubeadm-basic.images.tar.gz,把压缩包中的镜像导入到本地镜像仓库

[root@kmaster ~]# ll
total 216676
-rw-------. 1 root root      1391 Dec 22 04:42 anaconda-ks.cfg
drwxr-xr-x  2 root root       142 Dec 30 07:55 kubeadm-basic.images
-rw-r--r--  1 root root 221857746 Dec 30 08:01 kubeadm-basic.images.tar.gz
-rw-r--r--  1 root root       827 Dec 30 07:34 kubeadm.conf
-rw-r--r--  1 root root        20 Dec 30 07:00 kube-images.tar.gz
-rw-r--r--  1 root root       364 Dec 30 03:40 kubernetes.conf
[root@kmaster ~]# ll kubeadm-basic.images
total 692188
-rw-r--r-- 1 root root 122923520 Dec 30 07:54 apiserver.tar
-rw-r--r-- 1 root root  45364736 Dec 30 07:54 coredns.tar
-rw-r--r-- 1 root root 254677504 Dec 30 07:54 etcd.tar
-rw-r--r-- 1 root root 117107200 Dec 30 07:54 kubec-con-man.tar
-rw-r--r-- 1 root root    691712 Dec 30 07:55 pause.tar
-rw-r--r-- 1 root root 120377856 Dec 30 07:55 proxy.tar
-rw-r--r-- 1 root root  47643136 Dec 30 07:55 scheduler.tar

编写脚本问题,导入镜像包到本地docker镜像仓库:

# kubeadm 初始化 k8s 集群的时候,会从gce Google云中下载响应的镜像,且镜像相对比较大,下载比较慢
#1 导入镜像脚本代码(在任意目录下创建sh脚本文件:image-load.sh)
#! /bin/bash
#注意 镜像解压的目录位置
ls /root/kubeadm-basic.images > /tmp/images-list.txt
cd /root/kubeadm-basic.images
for i in $(cat /tmp/images-list.txt)
do
	docker load -i $i
done
rm -rf /tmp/images-list.txt

#2 修改权限,可执行权限
chmod 755 image-load.sh

#3 开始执行,镜像导入
./image-load.sh

#4 传输文件及镜像到其他node节点
#拷贝到knode1节点
scp -r image-load.sh kubeadm-basic.images root@knode1:/root/
#拷贝到knode2
scp -r image-load.sh kubeadm-basic.images root@knode2:/root/

5.3 node节点导入镜像

knode1导入镜像

[root@knode1 ~]# ./image-load.sh
Loaded image: k8s.gcr.io/kube-apiserver:v1.20.1
Loaded image: k8s.gcr.io/coredns:1.7.0
Loaded image: k8s.gcr.io/etcd:3.4.13-0
Loaded image: k8s.gcr.io/kube-controller-manager:v1.20.1
Loaded image: k8s.gcr.io/pause:3.2
Loaded image: k8s.gcr.io/kube-proxy:v1.20.1
Loaded image: k8s.gcr.io/kube-scheduler:v1.20.1
[root@knode1 ~]# docker images
REPOSITORY                           TAG        IMAGE ID       CREATED         SIZE
k8s.gcr.io/kube-proxy                v1.20.1    e3f6fcd87756   11 days ago     118MB
k8s.gcr.io/kube-apiserver            v1.20.1    75c7f7112080   11 days ago     122MB
k8s.gcr.io/kube-controller-manager   v1.20.1    2893d78e47dc   11 days ago     116MB
k8s.gcr.io/kube-scheduler            v1.20.1    4aa0b4397bbb   11 days ago     46.4MB
k8s.gcr.io/etcd                      3.4.13-0   0369cf4303ff   4 months ago    253MB
k8s.gcr.io/coredns                   1.7.0      bfe3a36ebd25   6 months ago    45.2MB
k8s.gcr.io/pause                     3.2        80d28bedfe5d   10 months ago   683kB

knode2导入镜像

[root@knode2 ~]# ./image-load.sh
Loaded image: k8s.gcr.io/kube-apiserver:v1.20.1
Loaded image: k8s.gcr.io/coredns:1.7.0
Loaded image: k8s.gcr.io/etcd:3.4.13-0
Loaded image: k8s.gcr.io/kube-controller-manager:v1.20.1
Loaded image: k8s.gcr.io/pause:3.2
Loaded image: k8s.gcr.io/kube-proxy:v1.20.1
Loaded image: k8s.gcr.io/kube-scheduler:v1.20.1
[root@knode2 ~]# docker images
REPOSITORY                           TAG        IMAGE ID       CREATED         SIZE
k8s.gcr.io/kube-proxy                v1.20.1    e3f6fcd87756   11 days ago     118MB
k8s.gcr.io/kube-apiserver            v1.20.1    75c7f7112080   11 days ago     122MB
k8s.gcr.io/kube-controller-manager   v1.20.1    2893d78e47dc   11 days ago     116MB
k8s.gcr.io/kube-scheduler            v1.20.1    4aa0b4397bbb   11 days ago     46.4MB
k8s.gcr.io/etcd                      3.4.13-0   0369cf4303ff   4 months ago    253MB
k8s.gcr.io/coredns                   1.7.0      bfe3a36ebd25   6 months ago    45.2MB
k8s.gcr.io/pause                     3.2        80d28bedfe5d   10 months ago   683kB

6 k8s部署

#初始化主节点----只需要在主节点执行

#1 拉去yaml资源配置文件
kubeadm config print init-defaults > kubeadm-config.yaml

#2 修改yaml资源文件
localAPIEndpoint:
	advertiseAddress: 192.168.8.121 # 注意: 修改配置文件的IP地址
kubernetesVersion: v1.20.1 # 注意:修改版本号,必须和kubectl版本保持一致
networking:
    dnsDomain: cluster.local
	# 指定flannel模型通信 pod网段地址,此网段和flannel网络一致
	podSubnet: "10.244.0.0/16"
	serviceSubnet: "10.96.0.0/12"
#指定使用ipvs网络进行通信
---
apiVersion: kubeadm.k8s.io/v1beta2
kind: kubeProxyConfiguration
featureGates:
	supportipvsproxymodedm.ymlvim kubeadm.yml: true
mode: ipvs

#3 初始化主节点,开始部署
kubeadm init --config=kubeadm-config.yaml --upload-certs | tee kubeadm-init.log
#注意:执行此命令,CPU核心数量必须大于1核,否则无法执行成功
W1230 09:44:35.116411    1495 strict.go:47] unknown configuration schema.GroupVersionKind{Group:"kubeadm.k8s.io", Version:"v1beta2", Kind:"kubeProxyConfiguration"} for scheme definitions in "k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm/scheme/scheme.go:31" and "k8s.io/kubernetes/cmd/kubeadm/app/componentconfigs/scheme.go:28"
[config] WARNING: Ignored YAML document with GroupVersionKind kubeadm.k8s.io/v1beta2, Kind=kubeProxyConfiguration
[init] Using Kubernetes version: v1.20.1
[preflight] Running pre-flight checks
        [WARNING SystemVerification]: this Docker version is not on the list of validated versions: 20.10.1. Latest validated version: 19.03
[preflight] Pulling images required for setting up a Kubernetes cluster
[preflight] This might take a minute or two, depending on the speed of your internet connection
[preflight] You can also perform this action in beforehand using 'kubeadm config images pull'
[certs] Using certificateDir folder "/etc/kubernetes/pki"
[certs] Generating "ca" certificate and key
[certs] Generating "apiserver" certificate and key
[certs] apiserver serving cert is signed for DNS names [kmaster kubernetes kubernetes.default kubernetes.default.svc kubernetes.default.svc.cluster.local] and IPs [10.96.0.1 192.168.8.121]
[certs] Generating "apiserver-kubelet-client" certificate and key
[certs] Generating "front-proxy-ca" certificate and key
[certs] Generating "front-proxy-client" certificate and key
[certs] Generating "etcd/ca" certificate and key
[certs] Generating "etcd/server" certificate and key
[certs] etcd/server serving cert is signed for DNS names [kmaster localhost] and IPs [192.168.8.121 127.0.0.1 ::1]
[certs] Generating "etcd/peer" certificate and key
[certs] etcd/peer serving cert is signed for DNS names [kmaster localhost] and IPs [192.168.8.121 127.0.0.1 ::1]
[certs] Generating "etcd/healthcheck-client" certificate and key
[certs] Generating "apiserver-etcd-client" certificate and key
[certs] Generating "sa" key and public key
[kubeconfig] Using kubeconfig folder "/etc/kubernetes"
[kubeconfig] Writing "admin.conf" kubeconfig file
[kubeconfig] Writing "kubelet.conf" kubeconfig file
[kubeconfig] Writing "controller-manager.conf" kubeconfig file
[kubeconfig] Writing "scheduler.conf" kubeconfig file
[kubelet-start] Writing kubelet environment file with flags to file "/var/lib/kubelet/kubeadm-flags.env"
[kubelet-start] Writing kubelet configuration to file "/var/lib/kubelet/config.yaml"
[kubelet-start] Starting the kubelet
[control-plane] Using manifest folder "/etc/kubernetes/manifests"
[control-plane] Creating static Pod manifest for "kube-apiserver"
[control-plane] Creating static Pod manifest for "kube-controller-manager"
[control-plane] Creating static Pod manifest for "kube-scheduler"
[etcd] Creating static Pod manifest for local etcd in "/etc/kubernetes/manifests"
[wait-control-plane] Waiting for the kubelet to boot up the control plane as static Pods from directory "/etc/kubernetes/manifests". This can take up to 4m0s
[apiclient] All control plane components are healthy after 8.503909 seconds
[upload-config] Storing the configuration used in ConfigMap "kubeadm-config" in the "kube-system" Namespace
[kubelet] Creating a ConfigMap "kubelet-config-1.20" in namespace kube-system with the configuration for the kubelets in the cluster
[upload-certs] Storing the certificates in Secret "kubeadm-certs" in the "kube-system" Namespace
[upload-certs] Using certificate key:
7ecfa579dfa66c0ea9c87146aa5130c1692b85a4d16cfc860473064a75c113c5
[mark-control-plane] Marking the node kmaster as control-plane by adding the labels "node-role.kubernetes.io/master=''" and "node-role.kubernetes.io/control-plane='' (deprecated)"
[mark-control-plane] Marking the node kmaster as control-plane by adding the taints [node-role.kubernetes.io/master:NoSchedule]
[bootstrap-token] Using token: abcdef.0123456789abcdef
[bootstrap-token] Configuring bootstrap tokens, cluster-info ConfigMap, RBAC Roles
[bootstrap-token] configured RBAC rules to allow Node Bootstrap tokens to get nodes
[bootstrap-token] configured RBAC rules to allow Node Bootstrap tokens to post CSRs in order for nodes to get long term certificate credentials
[bootstrap-token] configured RBAC rules to allow the csrapprover controller automatically approve CSRs from a Node Bootstrap Token
[bootstrap-token] configured RBAC rules to allow certificate rotation for all node client certificates in the cluster
[bootstrap-token] Creating the "cluster-info" ConfigMap in the "kube-public" namespace
[kubelet-finalize] Updating "/etc/kubernetes/kubelet.conf" to point to a rotatable kubelet client certificate and key
[addons] Applied essential addon: CoreDNS
[addons] Applied essential addon: kube-proxy

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/

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

kubeadm join 192.168.8.121:6443 --token abcdef.0123456789abcdef \
    --discovery-token-ca-cert-hash sha256:7459fa01464531734d3eee182461b77b043d31eff7df2233635654d7c199c947
[root@kmaster ~]#

参考kubeadm-config.yaml

apiVersion: kubeadm.k8s.io/v1beta2
bootstrapTokens:
- groups:
  - system:bootstrappers:kubeadm:default-node-token
  token: abcdef.0123456789abcdef
  ttl: 24h0m0s
  usages:
  - signing
  - authentication
kind: InitConfiguration
localAPIEndpoint:
  advertiseAddress: 192.168.8.121
  bindPort: 6443
nodeRegistration:
  criSocket: /var/run/dockershim.sock
  name: kmaster
  taints:
  - effect: NoSchedule
    key: node-role.kubernetes.io/master
---
apiServer:
  timeoutForControlPlane: 4m0s
apiVersion: kubeadm.k8s.io/v1beta2
certificatesDir: /etc/kubernetes/pki
clusterName: kubernetes
controllerManager: {}
dns:
  type: CoreDNS
etcd:
  local:
    dataDir: /var/lib/etcd
imageRepository: k8s.gcr.io
kind: ClusterConfiguration
kubernetesVersion: v1.20.1
networking:
  dnsDomain: cluster.local
  podSubnet: 10.244.0.0/16
  serviceSubnet: 10.96.0.0/12
scheduler: {}
---
apiVersion: kubeadm.k8s.io/v1beta2
kind: kubeProxyConfiguration
featureGates:
  supportipvsproxymodedm.ymlvim kubeadm.yml: true
  mode: ipvs

按照k8s指示,执行以下命令:

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

执行命令前:

kubectl get node
The connection to the server localhost:8080 was refused - did you specify the right host or port?

执行命令后

kubectl get node
NAME      STATUS     ROLES                  AGE     VERSION
kmaster   NotReady   control-plane,master   7m24s   v1.20.1

我们发现已经可以成功查询node节点信息了,但是节点的状态却是NotReady,不是Runing的状态。

原因是此时我们使用ipvs+flannel的方式进行网络通信,但是flannel网络插件还没有部署,因此节点状态为NotReady

7 flannel插件

#部署flannel网络插件---只需要在主节点执行
#1 下载flannel网络插件
wget https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml
#2 部署flannel
kubectl create -f kube-flannel.yml
#也可进行部署网络
kubectl apply -f https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml

验证

[root@kmaster ~]# kubectl get pod -n kube-system
NAME                              READY   STATUS    RESTARTS   AGE
coredns-74ff55c5b-5n6zs           1/1     Running   0          15m
coredns-74ff55c5b-r9469           1/1     Running   0          15m
etcd-kmaster                      1/1     Running   0          15m
kube-apiserver-kmaster            1/1     Running   0          15m
kube-controller-manager-kmaster   1/1     Running   0          15m
kube-flannel-ds-n4sbp             1/1     Running   0          89s
kube-proxy-t7bvn                  1/1     Running   0          15m
kube-scheduler-kmaster            1/1     Running   0          15m

8 追加Node节点

# 假如主节点以及其余工作节点,执行安装日志中的命令即可
# 查看日志文件
cat kubeadm-init.log
# 负责命令到其他几个node节点进行执行即可
kubeadm join 192.168.8.121:6443 --token abcdef.0123456789abcdef \
    --discovery-token-ca-cert-hash sha256:7459fa01464531734d3eee182461b77b043d31eff7df2233635654d7c199c947

knode1

kubeadm join 192.168.8.121:6443 --token abcdef.0123456789abcdef \
    --discovery-token-ca-cert-hash sha256:7459fa01464531734d3eee182461b77b043d31eff7df2233635654d7c199c947

knode2

kubeadm join 192.168.8.121:6443 --token abcdef.0123456789abcdef \
    --discovery-token-ca-cert-hash sha256:7459fa01464531734d3eee182461b77b043d31eff7df2233635654d7c199c947

9 验证状态

[root@kmaster ~]# kubectl get node
NAME      STATUS   ROLES                  AGE     VERSION
kmaster   Ready    control-plane,master   26m     v1.20.1
knode1    Ready    <none>                 5m37s   v1.20.1
knode2    Ready    <none>                 5m28s   v1.20.1
[root@kmaster ~]# kubectl get pod -n kube-system -o wide
NAME                              READY   STATUS    RESTARTS   AGE     IP              NODE                                                                                                        NOMINATED NODE   READINESS GATES
coredns-74ff55c5b-5n6zs           1/1     Running   0          27m     10.244.0.2      kmaster                                                                                                     <none>           <none>
coredns-74ff55c5b-r9469           1/1     Running   0          27m     10.244.0.3      kmaster                                                                                                     <none>           <none>
etcd-kmaster                      1/1     Running   0          27m     192.168.8.121   kmaster                                                                                                     <none>           <none>
kube-apiserver-kmaster            1/1     Running   0          27m     192.168.8.121   kmaster                                                                                                     <none>           <none>
kube-controller-manager-kmaster   1/1     Running   0          27m     192.168.8.121   kmaster                                                                                                     <none>           <none>
kube-flannel-ds-9td5g             1/1     Running   0          7m12s   192.168.8.122   knode1                                                                                                      <none>           <none>
kube-flannel-ds-n4sbp             1/1     Running   0          13m     192.168.8.121   kmaster                                                                                                     <none>           <none>
kube-flannel-ds-rvfbt             1/1     Running   0          7m3s    192.168.8.123   knode2                                                                                                      <none>           <none>
kube-proxy-knhtb                  1/1     Running   0          7m12s   192.168.8.122   knode1                                                                                                      <none>           <none>
kube-proxy-t7bvn                  1/1     Running   0          27m     192.168.8.121   kmaster                                                                                                     <none>           <none>
kube-proxy-vpxqm                  1/1     Running   0          7m3s    192.168.8.123   knode2                                                                                                      <none>           <none>
kube-scheduler-kmaster            1/1     Running   0          27m     192.168.8.121   kmaster                                                                                                     <none>           <none>

10 查看docker和k8s使用版本

[root@kmaster ~]# docker version
Client: Docker Engine - Community
 Version:           20.10.1
 API version:       1.41
 Go version:        go1.13.15
 Git commit:        831ebea
 Built:             Tue Dec 15 04:37:17 2020
 OS/Arch:           linux/amd64
 Context:           default
 Experimental:      true

Server: Docker Engine - Community
 Engine:
  Version:          20.10.1
  API version:      1.41 (minimum version 1.12)
  Go version:       go1.13.15
  Git commit:       f001486
  Built:            Tue Dec 15 04:35:42 2020
  OS/Arch:          linux/amd64
  Experimental:     false
 containerd:
  Version:          1.4.3
  GitCommit:        269548fa27e0089a8b8278fc4fc781d7f65a939b
 runc:
  Version:          1.0.0-rc92
  GitCommit:        ff819c7e9184c13b7c2607fe6c30ae19403a7aff
 docker-init:
  Version:          0.19.0
  GitCommit:        de40ad0

[root@kmaster ~]# kubectl version
Client Version: version.Info{Major:"1", Minor:"20", GitVersion:"v1.20.1", GitCommit:"c4d752765b3bbac2237bf87cf0b1c2e307844666", GitTreeState:"clean", BuildDate:"2020-12-18T12:09:25Z", GoVersion:"go1.15.5", Compiler:"gc", Platform:"linux/amd64"}
Server Version: version.Info{Major:"1", Minor:"20", GitVersion:"v1.20.1", GitCommit:"c4d752765b3bbac2237bf87cf0b1c2e307844666", GitTreeState:"clean", BuildDate:"2020-12-18T12:00:47Z", GoVersion:"go1.15.5", Compiler:"gc", Platform:"linux/amd64"}

注意:

使用docker版本20.10.1、Go版本1.13.15, 使用k8s版本1.20.1、Go版本1.15.5