CentOS7 operation and maintenance-PXE cooperates with Kickstart to realize unattended automatic installation | super detailed

PXE(Pre-boot operating environment) is Intera network boot technology developed by the company, working in C/Smode, allowing clients to download boot images from remote servers through the network, and load installation files or the entire operating system

Requirements for building

1. The client's network card must support the PXEprotocol (integrated BOOTROMchip), and the motherboard supports network boot. Generally most servers support it, only need BIOSto allow from Networkor LANstart in the settings
2. There is a DHCPserver in the network to automatically assign addresses and specify the location of the boot file for clients
3. The server must TFTPprovide the download of the boot image file through the service (Simple File Transfer Protocol)

Build a PXE remote installation server

PXEThe remote installation server integrates CentOS7installation sources, TFTPservices, and DHCPservices, and can send PXEbootloaders, Linuxkernels, boot menus and other data to the client bare metal , as well as provide installation files

1. Install TFTP and Xinetd and enable

TFTP(Simple File Transfer Protocol) is a UDPprotocol- based protocol for simple file transfer between client and server, suitable for small file transfer applications. TFTPThe service is managed by the xinetdservice by default , use UDPport69

xinetdIt is a new generation of network daemon service program, also called super server, commonly used to manage a variety of lightweight Internetservices

yum -y install tftp-server xinetd
vim /etc/xinetd.d/tftp

Modify the configuration
wait = {}value set to no
disable = {}value setno

service tftp
{
    
    
        socket_type             = dgram
        protocol                = udp
        wait                    = no
     	#wait no表示客户机可以多台一起连接，yes表示客户机只能一台一台连接
        user                    = root
        server                  = /usr/sbin/in.tftpd
        server_args             = -s /var/lib/tftpboot
        disable                 = no
        #disable no表示开启TFTP服务
        per_source              = 11
        cps                     = 100 2
        flags                   = IPv4
}

Open service

systemctl start tftp
systemctl start xinetd

2. Install and enable the DHCP service

yum -y install dhcp
vim /etc/dhcp/dhcpd.conf

:r /usr/share/doc/dhcp-4.2.5/dhcpd.conf.example
// 使用vi命令行指令将样式文件内容写入到当前文件
ddns-update-style none;
// 禁止动态更新
next-server IP;
// 指定 TFTP 服务器的地址
filename "pxelinux.0";
// 指定要下载的 PXE 引导程序的文件

subnet 网段 netmask 掩码 {
    
    
  range 地址池IP 地址池IP;
  option routers TFTP服务器IP;
}

Open service

systemctl start dhcpd

Three, prepare the kernel and image files

Mount the CD and enter the directory/mnt/images/pxeboot

mount /dev/cdrom /mnt
cd /mnt/images/pxeboot/

Will initrd.imgand vmlinuzcopied to tftpbootthe

cp initrd.img /var/lib/tftpboot/
cp vmlinuz /var/lib/tftpboot/

Fourth, prepare the PEX boot program

yum -y install syslinux
cp /usr/share/syslinux/pxelinux.0 /var/lib/tftpboot/

Five, install FTP|Prepare CentOS7 installation source

yum -y install vsftpd
mkdir /var/ftp/centos7
cp -rf /mnt/* /var/ftp/centos7/
// 将镜像复制其中
或者
mount /dev/sr0 /var/ftp/centos7
systemctl start vsftpd 
// 开启服务

Six, configure the boot menu file

Default boot menu file in TFTPthe root directory of the pxelinux.cfgsubdirectory, the file namedefault

mkdir /var/lib/tftpboot/pxelinux.cfg		  
vim /var/lib/tftpboot/pxelinux.cfg/default	

default auto 							#指定默认入口名称
prompt 1 								#设置是否等待用户选择，“1”表示等待用户控制

label auto								#图形安装（默认）引导入口，label 用来定义启动项
kernel vmlinuz							#kernel 和 append用来定义引导参数
append initrd=initrd.img method=ftp://192.168.1.1/centos7

label linux text						#文本安装引导入口
kernel vmlinuz
append text initrd=initrd.img method=ftp://192.168.1.1/centos7

label linux rescue						#救援模式引导入口
kernel vmlinuz
append rescue initrd=initrd.img method=ftp://192.168.1.1/centos7

systemctl stop firewalld.service        #关闭系统防火墙
setenforce 0                            #关闭系统安全机制

Seven, realize Kickstart unattended installation

① Prepare to install the answer file

yum install -y system-config-kickstart       #安装system-config-kickstart 工具

②Open the Kickstart configuration program

Use desktop mode to open

Use instructions to open

system-config-kickstart

③ Placement Kickstart

The default language is set to 中文（简体)
the time zone to Asia/Shanghai
set up roota password
advanced configuration check 安装后重启

installation method selected FTP
FTP server ftp://TFTPIP
FTP directorycentos7

Master Boot Record: 清除主引导记录
Partition: 删除所有现存分区
Disk Label:初始化磁盘标签

挂载点：/boot，文件系统类型：xfs，固定大小：500M
文件系统类型：swap，固定大小：4096M
挂载点：/home，文件系统类型：xfs，固定大小：4096M
挂载点：/，文件系统类型：xfs，使用磁盘上全部未使用空间

Adding network equipment ens33
network type to DHCP

the firewall as needed to select

post-install script

Check "Use Interpreter:/bin/bash

rm -rf /etc/yum.repos.d/*
echo '[local]
name=local
baseurl=ftp://192.168.1.1/centos7
enabled=1
gpgcheck=0' > /etc/yum.repos.d/local.repo

Save the file in the root directory

④Configuration package

vim ks.cfg

Add to the end

%packages
@^graphical-server-environment
@base
@core
@desktop-debugging
@development
@dial-up
@fonts
@gnome-desktop
@guest-agents
@guest-desktop-agents
@hardware-monitoring
@input-methods
@internet-browser
@multimedia
@print-client
@x11
chrony

%end

If you require minimal installation, you can copy the following

vim ks.cfg
%packages
@^minimal
%end

Copy /root/anaconda-ks.cfgthe package installation script of /var/ftp/ks.cfgto for desktop installation

cp /root/ks.cfg /var/ftp/ks.cfg

⑤Add ks boot parameters to the boot menu file

vim /var/lib/tftpboot/pxelinux.cfg/default	

Eight, create a new virtual machine inspection

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