在工作中，安装一台linux系统的计算机很容易，也很快，但是安装100台甚至1000台那就要累死人了，这个时候可以使用PXE方式也就是网刻的方式来部署，windows下也可以这样做，很多网吧都是这样干的，不过，windows系统下还有个SID（安全标示符）需要重新生成下！先来说说什么是PXE吧！
PXE(Pre-boot Execution Environment)是由Intel设计的协议，它可以使计算机通过网络启动。协议分为client和server两端，PXE client在网卡的ROM中，当计算机引导时，BIOS把PXE client调入内存执行，并显示出命令菜单，经用户选择后，PXE client将放置在远端的操作系统通过网络下载到本地运行。PXE协议的成功运行需要解决以下两个问题：
1:既然是通过网络传输，那么计算机在启动时，它的IP地址由谁来配置；
2:通过什么协议下载Linux内核和根文件系统
对于第一个问题，可以通过DHCP Server解决，由DHCP server来给PXE client分配一个IP地址，DHCPServer是用来给DHCP Client动态分配IP地址的协议，不过由于这里是给PXE Client分配IP地址，所以在配置DHCP Server时，需要增加相应的PXE特有配置。
至于第二个问题，在PXE client所在的ROM中，已经存在了TFTP Client。PXE Client使用TFTP Client，通过TFTP协议到TFTP Server上下载所需的文件。
2:通过什么协议下载Linux内核和根文件系统
对于第一个问题，可以通过DHCP Server解决，由DHCP server来给PXE client分配一个IP地址，DHCPServer是用来给DHCP Client动态分配IP地址的协议，不过由于这里是给PXE Client分配IP地址，所以在配置DHCP Server时，需要增加相应的PXE特有配置。
至于第二个问题，在PXE client所在的ROM中，已经存在了TFTP Client。PXE Client使用TFTP Client，通过TFTP协议到TFTP Server上下载所需的文件。
通过yum安装dhcp和tftp
[root@centos5 /]# rpm -qa |grep tftp-server-*
[root@centos5 /]# rpm -qa |grep dhcp
dhcpv6-client-1.0.10-4.el5
[root@centos5 /]# rpm -qa |grep tftp-server-*
[root@centos5 /]# rpm -qa |grep dhcp
dhcpv6-client-1.0.10-4.el5
[root@centos5 /]# yum -y install tftp-server dhcp
Loaded plugins: fastestmirror
Loading mirror speeds from cached hostfile
* base: ftp.hostrino.com
* updates: mirror.nus.edu.sg
* addons: ftp.hostrino.com
* extras: ftp.hostrino.com
Setting up Install Process
Parsing package install arguments
Resolving Dependencies
--> Running transaction check
---> Package dhcp.i386 12:3.0.5-18.el5 set to be updated
---> Package tftp-server.i386 0:0.42-3.1.el5.centos set to be updated
--> Finished Dependency Resolution
Loaded plugins: fastestmirror
Loading mirror speeds from cached hostfile
* base: ftp.hostrino.com
* updates: mirror.nus.edu.sg
* addons: ftp.hostrino.com
* extras: ftp.hostrino.com
Setting up Install Process
Parsing package install arguments
Resolving Dependencies
--> Running transaction check
---> Package dhcp.i386 12:3.0.5-18.el5 set to be updated
---> Package tftp-server.i386 0:0.42-3.1.el5.centos set to be updated
--> Finished Dependency Resolution
Dependencies Resolved
================================================================================
Package Arch Version Repository Size
================================================================================
Installing:
dhcp i386 12:3.0.5-18.el5 base 875 k
tftp-server i386 0.42-3.1.el5.centos base 27 k
Package Arch Version Repository Size
================================================================================
Installing:
dhcp i386 12:3.0.5-18.el5 base 875 k
tftp-server i386 0.42-3.1.el5.centos base 27 k
Transaction Summary
================================================================================
Install 2 Package(s)
Update 0 Package(s)
Remove 0 Package(s)
================================================================================
Install 2 Package(s)
Update 0 Package(s)
Remove 0 Package(s)
Total download size: 902 k
Downloading Packages:
(1/2): tftp-server-0.42-3 100% |=========================| 27 kB 00:21
(2/2): dhcp-3.0.5-18.el5. 100% |=========================| 875 kB 02:28
Running rpm_check_debug
Running Transaction Test
Finished Transaction Test
Transaction Test Succeeded
Running Transaction
Installing : tftp-server [1/2]
Installing : dhcp [2/2]
Downloading Packages:
(1/2): tftp-server-0.42-3 100% |=========================| 27 kB 00:21
(2/2): dhcp-3.0.5-18.el5. 100% |=========================| 875 kB 02:28
Running rpm_check_debug
Running Transaction Test
Finished Transaction Test
Transaction Test Succeeded
Running Transaction
Installing : tftp-server [1/2]
Installing : dhcp [2/2]
Installed: dhcp.i386 12:3.0.5-18.el5 tftp-server.i386 0:0.42-3.1.el5.centos
Complete!
[root@centos5 /]# vi /etc/xinetd.d/tftp (编辑tftp配置文件如下)
# default: off
# description: The tftp server serves files using the trivial file transfer \
# protocol. The tftp protocol is often used to boot diskless \
# workstations, download configuration files to network-aware printers, \
# and to start the installation process for some operating systems.
service tftp
{
socket_type = dgram
protocol = udp
wait = yes
user = root
server = /usr/sbin/in.tftpd
server_args = -u nobody -s /tftpboot
disable = no
per_source = 11
cps = 100 2
flags = IPv4
}
Complete!
[root@centos5 /]# vi /etc/xinetd.d/tftp (编辑tftp配置文件如下)
# default: off
# description: The tftp server serves files using the trivial file transfer \
# protocol. The tftp protocol is often used to boot diskless \
# workstations, download configuration files to network-aware printers, \
# and to start the installation process for some operating systems.
service tftp
{
socket_type = dgram
protocol = udp
wait = yes
user = root
server = /usr/sbin/in.tftpd
server_args = -u nobody -s /tftpboot
disable = no
per_source = 11
cps = 100 2
flags = IPv4
}
[root@centos5 /]# vi /etc/dhcpd.conf （编辑dhcp配置文件如下）
#
# DHCP Server Configuration file.
# see /usr/share/doc/dhcp*/dhcpd.conf.sample
#
option domain-name "yang.com";
default-lease-time 6000;
max-lease-time 11400;
authourtative;
next-server 192.168.0.200; （需要加上这个参数来指定DHCP SERVER的IP，否则可能会出现错误）
ddns-update-style ad-hoc;
log-facility local7;
subnet 192.168.0.0 netmask 255.255.255.0{
range 192.168.0.10 192.168.0.100;
option domain-name-servers 192.168.0.200;
option domain-name "yang.com";
option netbios-name-servers 192.168.0.200;
option routers 192.168.0.1;
option broadcast-address 192.168.0.255;
default-lease-time 6000;
max-lease-time 11400;
filename "/pxelinux.0";
}
#
# DHCP Server Configuration file.
# see /usr/share/doc/dhcp*/dhcpd.conf.sample
#
option domain-name "yang.com";
default-lease-time 6000;
max-lease-time 11400;
authourtative;
next-server 192.168.0.200; （需要加上这个参数来指定DHCP SERVER的IP，否则可能会出现错误）
ddns-update-style ad-hoc;
log-facility local7;
subnet 192.168.0.0 netmask 255.255.255.0{
range 192.168.0.10 192.168.0.100;
option domain-name-servers 192.168.0.200;
option domain-name "yang.com";
option netbios-name-servers 192.168.0.200;
option routers 192.168.0.1;
option broadcast-address 192.168.0.255;
default-lease-time 6000;
max-lease-time 11400;
filename "/pxelinux.0";
}
[root@centos5 /]# cat /etc/exports （配置NFS共享）
/mnt 192.168.0.0/24(ro,sync)
/mnt 192.168.0.0/24(ro,sync)
下面这段是照着boobooke上面写的，应该是linux专门针对PXE的一些文件和目录设置
[root@centos5 ~]# mkdir /tftpboot
[root@centos5 ~]# cp /usr/lib/syslinux/pxelinux.0 /tftpboot/
[root@centos5 ~]# mount /dev/cdrom /mnt/ （挂载关盘）
mount: block device /dev/cdrom is write-protected, mounting read-only
[root@centos5 ~]# cp /usr/lib/syslinux/pxelinux.0 /tftpboot/
[root@centos5 ~]# mount /dev/cdrom /mnt/ （挂载关盘）
mount: block device /dev/cdrom is write-protected, mounting read-only
[root@centos5 /]# cp /mnt/isolinux/* /tftpboot/
[root@centos5 /]# mkdir /tftpboot/pxelinux.cfg
[root@centos5 /]# cp /tftpboot/isolinux.cfg /tftpboot/pxelinux.cfg/
[root@centos5 /]# cd /tftpboot/pxelinux.cfg/
[root@centos5 pxelinux.cfg]# ls
isolinux.cfg
[root@centos5 pxelinux.cfg]# mv isolinux.cfg default
[root@centos5 pxelinux.cfg]# ls
default
[root@centos5 /]# mkdir /tftpboot/pxelinux.cfg
[root@centos5 /]# cp /tftpboot/isolinux.cfg /tftpboot/pxelinux.cfg/
[root@centos5 /]# cd /tftpboot/pxelinux.cfg/
[root@centos5 pxelinux.cfg]# ls
isolinux.cfg
[root@centos5 pxelinux.cfg]# mv isolinux.cfg default
[root@centos5 pxelinux.cfg]# ls
default
[root@centos5 /]# service dhcpd start （启动相关服务）
Starting dhcpd: [ OK ]
Starting dhcpd: [ OK ]
[root@centos5 /]# service xinetd start
Starting xinetd: [ OK ]
[root@centos5 /]# service nfs start
Starting NFS services: [ OK ]
Starting NFS quotas: [ OK ]
Starting NFS daemon: [ OK ]
Starting NFS mountd: [ OK ]
Starting RPC idmapd: [ OK ]
Starting NFS services: [ OK ]
Starting NFS quotas: [ OK ]
Starting NFS daemon: [ OK ]
Starting NFS mountd: [ OK ]
Starting RPC idmapd: [ OK ]
[root@centos5 /]# netstat -nupl |grep 67 （查看相应的端口）
udp 0 0 0.0.0.0:67 0.0.0.0:*
udp 0 0 0.0.0.0:67 0.0.0.0:*
6400/dhcpd
[root@centos5 /]# netstat -nupl |grep 69
udp 0 0 0.0.0.0:769 0.0.0.0:*
[root@centos5 /]# netstat -nupl |grep 69
udp 0 0 0.0.0.0:769 0.0.0.0:*
6528/rpc.rquotad
udp 0 0 0.0.0.0:69 0.0.0.0:*
udp 0 0 0.0.0.0:69 0.0.0.0:*
6434/xinetd
udp 0 0 :::32769 :::*
udp 0 0 :::32769 :::*
2271/avahi-daemon:
以上的设置都是针对PXE服务器端的，下面就来测试下客户端能否正常的安装系统
可以看到客户端获取到了IP了
需要选择使用NFS镜像
使用DHCP方式获取IP，这里只启用IPV4
设置NFS参数
接下来的安装步骤就不截图了，下面是输入root用户的密码
这里只选择装个最基本的base,其他的什么都不装
大概10分钟的时间，安装过程就可结束
[root@centos5 /]# tail -f /var/log/messages （在PXE服务器上查看到的日志信息）
Feb 1 01:30:08 centos5 dhcpd: DHCPDISCOVER from 00:0c:29:03:09:5f via eth0
Feb 1 01:30:09 centos5 dhcpd: DHCPOFFER on 192.168.0.100 to 00:0c:29:03:09:5f via eth0
Feb 1 01:30:09 centos5 dhcpd: DHCPREQUEST for 192.168.0.100 (192.168.0.200) from 00:0c:29:03:09:5f via eth0
Feb 1 01:30:09 centos5 dhcpd: DHCPACK on 192.168.0.100 to 00:0c:29:03:09:5f via eth0
Feb 1 01:30:47 centos5 mountd[3403]: authenticated mount request from 192.168.0 .100:656 for /mnt (/mnt)
Feb 1 01:42:57 centos5 xinetd[3604]: EXIT: tftp status=0 pid=3606 duration=2596(sec)
Feb 1 01:43:26 centos5 init: Trying to re-exec init
