openstack部署中操作系统安装是个问题，虽然有很多解决方案，但是都要安装一些软件，我试验一些基于操作系统的方法（注意操作版本），步骤：
1、安装配置DHCP；
2、安装配置TFTP与syslinux中的模块
3、PXE启动与安装
下面是详细内容：
cat dhcpd.conf
#
# DHCP Server Configuration file.
# see /usr/share/doc/dhcp*/dhcpd.conf.sample
#
ddns-update-style interim;
ignore client-updates;
allow booting;
allow bootp;
subnet 10.12.28.0 netmask 255.255.252.0 {
# --- default gateway
deny unknown-clients;
option routers 10.12.28.1;
option subnet-mask 255.255.252.0;
option nis-domain "test-iaas.org";
option domain-name "test-iaas.org";
option domain-name-servers 10.12.5.134;
option time-offset -18000; # Eastern Standard Time
option ntp-servers 10.12.28.4;
range dynamic-bootp 10.12.29.6 10.12.29.160;
default-lease-time 21600;
max-lease-time 43200;
#pxe install part
next-server 10.12.5.134;
filename "/linux58/pxelinux.0";
# we want the nameserver to appear at a fixed address
host s29dot7 { next-server 10.12.5.134; hardware ethernet 00:25:90:2c:9f:40; fixed-address 10.12.29.7; }
host s29dot160 { next-server 10.12.5.134; hardware ethernet 00:25:90:2c:9f:44; fixed-address 10.12.29.160; }
}
cat /tftpboot/boot.msg
splash.lss
- Press the 01<ENTER>07 key to begin the installation process.
cat /tftpboot/pxelinux.cfg/default
#default vesamenu.c32
default linux
prompt 1
timeout 6000
display boot.msg
menu background splash.jpg
menu title Welcome to linux
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 linux
menu label ^Install or upgrade an existing system
menu default
kernel vmlinuz
append initrd=initrd.img
label vesa
menu label Install system with ^basic video driver
kernel vmlinuz
append initrd=initrd.img xdriver=vesa 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 -
ll /tftpboot/vmlinuz /tftpboot/initrd.img /tftpboot/pxelinux.0
-rw-r--r-- 1 root root 30754349 06-07 16:49 /tftpboot/initrd.img
-rw-r--r-- 1 root root 26828 06-07 17:05 /tftpboot/pxelinux.0
-rwxr-xr-x 1 root root 3938288 06-07 16:49 /tftpboot/vmlinuz
