目前集群状态
- 如K8S 集群搭建中规划的集群一样
Master | node01 | node02 | |
---|---|---|---|
IP | 192.168.100.100 | 192.168.100.101 | 192.168.100.102 |
OS | Cent OS 7.9 | Cent OS 7.9 | Cent OS 7.9 |
- 目前打算新增节点node03
Master | node01 | node02 | node03 | |
---|---|---|---|---|
IP | 192.168.100.100 | 192.168.100.101 | 192.168.100.102 | 192.168.100.103 |
OS | Cent OS 7.9 | Cent OS 7.9 | Cent OS 7.9 | Cent OS 7.9 |
1. 安装虚拟机
1.1 硬件分配
- CPU : 1 颗 2 核 CPU
- 内存:2048 MB
- 磁盘:50 GB
- 其它:默认
1.2 为设备安装OS
Cent OS 7.9 阿里云ISO链接
- 加载系统时,选择基础服务器
[root@Master ~]# cat /etc/redhat-release
CentOS Linux release 7.9.2009 (Core)
1.3 配置网卡
1.3.1 node 03
op | key | value | 位置 |
---|---|---|---|
修改 | BOOTPROTO | none | 4 |
修改 | ONBOOT | yes | 15 |
新增 | IPADDR | 192.168.100.103 | |
新增 | PREFIX | 24 | |
新增 | GATEWAY | 192.168.100.2 | |
新增 | DNS1 | 223.5.5.5 | |
新增 | IPV6_PRIVACY | no |
[root@node03 ~]# vim /etc/sysconfig/network-scripts/ifcfg-ens33
TYPE=Ethernet
PROXY_METHOD=none
BROWSER_ONLY=no
BOOTPROTO=none
DEFROUTE=yes
IPV4_FAILURE_FATAL=no
IPV6INIT=yes
IPV6_AUTOCONF=yes
IPV6_DEFROUTE=yes
IPV6_FAILURE_FATAL=no
IPV6_ADDR_GEN_MODE=stable-privacy
NAME=ens33
UUID=eb4335b9-98b7-4c63-ba0d-a25fa63aa5f5
DEVICE=ens33
ONBOOT=yes
IPADDR=192.168.100.103
PREFIX=24
GATEWAY=192.168.100.2
DNS1=223.5.5.5
IPV6_PRIVACY=no
1.4 修改hosts文件
1.3.1 Master
[root@Master ~]# vim /etc/hosts
127.0.0.1 localhost localhost.localdomain localhost4 localhost4.localdomain4
::1 localhost localhost.localdomain localhost6 localhost6.localdomain6
192.168.100.100 Master
192.168.100.101 node01
192.168.100.102 node02
192.168.100.103 node03
1.3.2 node 01
[root@node01 ~]# vim /etc/hosts
127.0.0.1 localhost localhost.localdomain localhost4 localhost4.localdomain4
::1 localhost localhost.localdomain localhost6 localhost6.localdomain6
192.168.100.100 Master
192.168.100.101 node01
192.168.100.102 node02
192.168.100.103 node03
1.3.3 node 02
[root@node02 ~]# vim /etc/hosts
127.0.0.1 localhost localhost.localdomain localhost4 localhost4.localdomain4
::1 localhost localhost.localdomain localhost6 localhost6.localdomain6
192.168.100.100 Master
192.168.100.101 node01
192.168.100.102 node02
192.168.100.103 node03
1.3.3 node 03
[root@node03 ~]# vim /etc/hosts
127.0.0.1 localhost localhost.localdomain localhost4 localhost4.localdomain4
::1 localhost localhost.localdomain localhost6 localhost6.localdomain6
192.168.100.100 Master
192.168.100.101 node01
192.168.100.102 node02
192.168.100.103 node03
2. 修改内核
建议安装XShell, XShell 官网
2.2~2.7的命令,此次仅node 03上同时执行,2.1除外
- 在XShell上,单击右键->发送键输入到->所有会话
2.1 时间同步
2.1 的命令建议Master、node 01、node 02、node 03上同时执行
# 启动chronyd服务
[root@node03 ~]# systemctl start chronyd
# 设置chronyd服务开机自启
[root@node03 ~]# systemctl enable chronyd
# 验证时间
[root@node03 ~]# date
2.2 禁用iptables&firewalld
[root@node03 ~]# systemctl stop firewalld
[root@node03 ~]# systemctl disable firewalld
[root@node03 ~]# systemctl stop iptables
[root@node03 ~]# systemctl disable iptables
2.3 禁用SELinux
- 命令getenforce可查看是否开启
# 仅修改SELINUX值为disabled
[root@node03 ~]# vim /etc/selinux/config# This file controls the state of SELinux on the system.
# SELINUX= can take one of these three values:
# enforcing - SELinux security policy is enforced.
# permissive - SELinux prints warnings instead of enforcing.
# disabled - No SELinux policy is loaded.
# SELINUX=enforcing
SELINUX=disabled
# SELINUXTYPE= can take one of three values:
# targeted - Targeted processes are protected,
# minimum - Modification of targeted policy. Only selected processes are protected.
# mls - Multi Level Security protection.
SELINUXTYPE=targeted
2.4 禁用swap
# 将最后一行注释掉
[root@node03 ~]# vim /etc/fstab#
# /etc/fstab
# Created by anaconda on Sun Jun 23 11:17:14 2024
#
# Accessible filesystems, by reference, are maintained under '/dev/disk'
# See man pages fstab(5), findfs(8), mount(8) and/or blkid(8) for more info
#
/dev/mapper/centos-root / xfs defaults 0 0
UUID=83ed761a-3ce3-46d3-889c-e4078b53b0c1 /boot xfs defaults 0 0
# /dev/mapper/centos-swap swap swap defaults 0 0
# 查看swap是否关闭,如刚刚修改,需要重启才能生效,此时暂不重启,2.7会重启
[root@node03 ~]# free -m
2.5 修改linux内核参数
[root@node03 ~]# vim /etc/sysctl.d/kubernetes.conf
# 添加网桥过滤和地址转发功能
# 在/etc/sysctl.d/kubernetes.conf文件中添加如下内容
net.bridge.bridge-nf-call-ip6tables = 1
net.bridge.bridge-nf-call-iptables = 1
net.ipv4.ip_forward = 1# 重新加载配置
[root@node03 ~]# sysctl -p
# 加载网桥过滤模块
[root@node03 ~]# modprobe br_netfilter
# 查看网桥过滤模块是否加载成功
[root@node03 ~]# lsmod | grep br_netfilter
2.6 配置ipvs功能
此处可能需要配置yum源
[root@node03 ~]# mkdir -p /etc/yum.repos.d/backup/
# 备份本地yum包
[root@node03 ~]# mv /etc/yum.repos.d/*.repo /etc/yum.repos.d/backup/
[root@node03 ~]# wget -O /etc/yum.repos.d/CentOs-Base.repo http://mirrors.aliyun.com/repo/Centos-7.repo
[root@node03 ~]# yum clean all
[root@node03 ~]# yum makecache
在k8s中Service有两种代理模型:
- 基于iptables的
- 基于ipvs的
本人使用ipvs,下面手动载入ipvs模块
[root@node03 ~]# yum install ipset ipvsadm -y
[root@node03 ~]# vim /etc/sysconfig/modules/ipvs.modulesmodprobe
#!/bin/bash
modprobe -- ip_vs
modprobe -- ip_vs_rr
modprobe -- ip_vs_wrr
modprobe -- ip_vs_sh
modprobe -- nf_conntrack_ipv4
[root@node03 ~]# chmod +x /etc/sysconfig/modules/ipvs.modulesmodprobe
[root@node03 ~]# /bin/bash /etc/sysconfig/modules/ipvs.modulesmodprobe
[root@node03 ~]# lsmod | grep -e ip_vs -e nf_conntrack_ipv4
2.7 重启
[root@node03 ~]# reboot
注意:2.2~2.7的命令仅在node 03上执行,2.1除外(在全部节点同时执行)
3. 安装Docker
3.1~3.5的命令,仅在node 03上执行
3.1 切换镜像源
[root@node03 ~]# wget https://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo -O /etc/yum.repos.d/docker-ce.repo
3.2 查看镜像源中docker版本
[root@node03 ~]# yum list docker-ce --showduplicates
3.3 安装docker-ce
- 若不指定–setopt=obsoletes=0 参数,yum自动安装更高版本
[root@node03 ~]# yum install --setopt=obsoletes=0 docker-ce-18.06.3.ce-3.el7 -y
3.4 添加配置文件
- Docker默认使用Cgroup Driver为cgroupfs
- K8s推荐使用systemd替代cgroupfs
[root@node03 ~]# mkdir /etc/docker
[root@node03 ~]# vim /etc/docker/daemon.json
{"exec-opts":["native.cgroupdriver=systemd"],"registry-mirrors":["https://kn0t2bca.mirror.aliyuncs.com"]
}
3.5 启动docker
[root@node03 ~]# systemctl restart docker
[root@node03 ~]# systemctl enable docker
# 查看docker是否将CGroupDriver更新为systemd
[root@node03 ~]# docker info
注意:3.1~3.5的命令仅在node03上执行
4. 安装kubernetes组件
4.1~4.4的命令,仅在node03 上执行
4.1 更换K8s镜像源为阿里镜像源
[root@node03 ~]# vim /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
4.2 安装kubeadm、kubelet、kubectl
[root@node03 ~]# yum install --setopt=obsoletes=0 kubeadm-1.17.4-0 kubelet-1.17.4-0 kubectl-1.17.4-0 -y
4.3 配置kubelet的cgroup
# 配置kubelet的cgroup
[root@node03 ~]# vim /etc/sysconfig/kubelet
KUBELET_CGROUP_ARGS="--cgroup-driver=systemd"
KUBE_PROXY_MODE="ipvs"
4.4 kubelet开机自启
[root@node03 ~]# systemctl enable kubelet
注意:4.1~4.4的命令仅在node03上执行
5. 准备集群镜像
5.1~5.2的命令,仅在node03上执行
5.1 查看集群所需镜像
[root@node03 ~]# kubeadm config images list
5.2 手动编写脚本,拉取镜像
[root@node03 ~]# vim k8s.repo
#!/bin/bash
images=(
kube-apiserver:v1.17.4
kube-controller-manager:v1.17.4
kube-scheduler:v1.17.4
kube-proxy:v1.17.4
pause:3.1
etcd:3.4.3-0
coredns:1.6.5
)
for imageName in ${images[@]} ; dodocker pull registry.cn-hangzhou.aliyuncs.com/google_containers/$imageNamedocker tag registry.cn-hangzhou.aliyuncs.com/google_containers/$imageName k8s.gcr.io/$imageNamedocker rmi registry.cn-hangzhou.aliyuncs.com/google_containers/$imageName
done
[root@node03 ~]# chmod +x k8s.repo
[root@node03 ~]# ./k8s.repo
[root@node03 ~]# docker images
注意:5.1~5.2的命令仅在node03 上执行
6. 将node03加入集群
6.1 node03加载镜像
- worker节点目前有哪些镜像,node03就要有哪些镜像
- worker节点指node01、node02、node03
6.2 node03加入集群
仅在node 03节点上操作
6.2.1 场景一:距离最近一次集群中加入新节点不超过24h
- 可通过查看最近一次加入集群的新节点的历史命令,复制到目前要加入的新节点node03下执行,命令如下所示
kubeadm join 192.168.100.100:6443 --token gkdzgt.v73dx3hhiczgmeud --discovery-token-ca-cert
6.2.2 场景二:距离最近一次集群中加入新节点超过24h
kubeadm token create --print-join-command
6.3 验证node03是否加入集群
仅在Master节点上操作
kubectl get nodes -o wide