BootStraping：系统提供（OS Provision）
pxe –> preboot excution environment, Intel
cobbler –> Cobbler is a network install server. Cobbler supports PXE, ISO virtualized installs, and re-installing existing Linux machines.
pxe：
dhcp service (ip/nemask, gw, dns; filename, next-server)
tftp server (bootloader, kernel, initrd)
yum repository (ftp, http, https, nfs)
kickstart
dhcp server：
DHCP：Dynamic Host Configuration Protocol
arp –> address resolving Protocol
IP –> MAC
rarp –> reverse arp
MAC –> IP
bootp –> boot protocol
dhcp: lease time, bootp
工作流程：广播
(1) Client：dhcp discover
(2) Server: dhcp offer(IP/Netmask, GW, DNS Server, NTP Server, Wins Server, …)
(3) Client：dhcp request
(4) Server：dhcp ack
lease time：租约期限；
续租：50%, 75%, 87.5%, 93.75%
dhcp discover，…
续租：
dhcp request
dhcp ack|nak
实现：
dhcp (isc.org) – The dhcp package provides the ISC DHCP service and relay agent.
dnsmasq (dns, dhcp) – Dnsmasq is lightweight, easy to configure DNS forwarder and DHCP server. It is designed to provide DNS and, optionally, DHCP, to a small network.
dhcp：
程序环境：
dhcp server：
/usr/sbin/dhcpd
IPV4网络：
/etc/dhcp/dhcpd.conf
/usr/lib/systemd/system/dhcpd.service
IPV6网络：
/etc/dhcp/dhcpd6.conf
/usr/lib/systemd/system/dhcpd6.service
dhcrelay：
/usr/sbin/dhcrelay
/usr/lib/systemd/system/dhcrelay.service
监听的地址和端口：
Server： 67/udp
Client： 68/udp
配置文件：/etc/dhcp/dhcpd.conf
配置指令：
option选项：配置给客户端的相信息
指令：定义dhcp server的工作特性
配置有级别之分：
全局配置
子网配置
主机配置
常用的配置：
default-lease-time 600;
max-lease-time 7200;
option domain-name "search_domain.tld";
option domain-name-servers DNS_SERVER1, DNS_SERVER2, DNS_SERVER3;
option routers GW1, GW2, …;
option broadcast-address BROADCAST_ADDRESS;
subnet NETWORK netmask MASK {
range START_IP END_IP;
} 定义网络作用域，即一个子网，主要用于指明地址池；
host passacaglia {
hardware ethernet 0:0:c0:5d:bd:95;
fixed-address IP_ADDR;
}
其它指令：
filename：指明引导文件名称；
next-server：指明引导文件所在的服务器的主机IP；
示例：
filename “pxelinux.0";
next-server 10.1.0.6; #指明tftp server地址
tftp server：
# yum install tftp-server tftp
CentOS 7:
systemctl start tftp.socket
CentOS 6:
chkconfig tftp on
service xinetd restart
69/udp
默认的文件根目录：/var/lib/tftpboot/
vsftpd server:
用作yum repository
# yum install vsftpd tftp
CentOS 7:
systemctl start vsftpd
CentOS 6:
chkconfig vsftpd on
把光盘挂载至/var/ftp/pub目录下，或者把光盘中的所有内容cp到/var/ftp/pub目录下
配置PXE环境：
CentOS 7： <基于http服务来提供yum repository>
yum -y install syslinux httpd mkdir /var/www/html/centos/7/x86_64 mount /dev/cdrom /var/www/html/centos/7/x86_64 #把光盘挂载至此目录 获取一个kickstart文件，放于/var/www/html目录下 cp /usr/share/syslinux/pxelinux.0 /var/lib/tftpboot/ cp /media/cdrom/images/pxeboot/{vmlinuz,initrd.img} /var/lib/tftpboot cp /usr/share/syslinux/{chain.c32,mboot.c32,menu.c32,memdisk} /var/lib/tftpboot mkdir /var/lib/tftpboot/pxelinux.cfg/ vim /var/lib/tftpboot/pxelinux.cfg/default default menu.c32 prompt 5 timeout 30 MENU TITLE CentOS 7 PXE Menu LABEL linux MENU LABEL Install CentOS 7 x86_64 KERNEL vmlinuz APPEND initrd=initrd.img inst.repo=http://10.1.43.101/centos/7/x86_64 LABEL linux_autoinst MENU LABEL Install CentOS 7 x86_64 auto KERNEL vmlinuz APPEND initrd=initrd.img inst.repo=http://10.1.43.101/centos/7/x86_64 ks=http://10.1.43.101/centos7.cfg
CentOS 6:
获取一个kickstart文件放在/var/ftp目录下 yum -y install syslinux-nolinux #提供了/usr/share/syslinux/pxelinux.0文件 mount /dev/cdrom /var/ftp/pub cp /usr/share/syslinux/pxelinux.0 /var/lib/tftpboot/ cp /var/ftp/pub/images/pxeboot/{vmlinuz,initrd.img} /var/lib/tftpboot/ cp /var/ftp/pub/isolinux/{boot.msg,vesamenu.c32,splash.jpg} /var/lib/tftpboot/ mkdir /var/lib/tftpboot/pxelinux.cfg/ cp /media/cdrom/isolinux/isolinux.cfg /var/lib/tftpboot/pxelinux.cfg/default /var/lib/tftpboot/pxelinux.cfg/default 内容如下所示： display boot.msg menu background splash.jpg menu title Welcome to CentOS 6.7 MageEdu! menu color border 0 #ffffffff #00000000 menu color sel 7 #ffffffff #ff000000 menu color title 0 #ffffffff #00000000 menu color tabmsg 0 #ffffffff #00000000 menu color unsel 0 #ffffffff #00000000 menu color hotsel 0 #ff000000 #ffffffff menu color hotkey 7 #ffffffff #ff000000 menu color scrollbar 0 #ffffffff #00000000 label autoinst menu label ^Auto Install CentOS menu default kernel vmlinuz append initrd=initrd.img ks=ftp://10.1.43.101/centos6.cfg label linux menu label ^Install or upgrade an existing system kernel vmlinuz append initrd=initrd.img label vesa menu label Install system with ^basic video driver kernel vmlinuz append initrd=initrd.img nomodeset label rescue menu label ^Rescue installed system kernel vmlinuz append initrd=initrd.img rescue label local menu label Boot from ^local drive localboot 0xffff label memtest86 menu label ^Memory test kernel memtest append -
原创文章，作者：megedugao，如若转载，请注明出处：http://www.178linux.com/58319
