build pxe enviorment dhcp + tftp

first deploy a unbunt without unknow passwd, then deploy a unbuntu with some unknown error, that failed to stat tftp server.
then finally, dhcpd, tftp service start successfullly, the latest I10_pxe is illed.
so take the old I10_pxe with latest I10_wnos, and I get back my way.

the way to build tftpd sever:

1. sudo apt-get install tftpd tftp openbsd-inetd

2. sudo  vi /etc/inetd.conf

#:BOOT: TFTP service is provided primarily for booting. Most sites
# run this only on machines acting as "boot servers."
#tftp dgram udp wait nobody /usr/sbin/tcpd /usr/sbin/in.tftpd /srv/tftp  (/srv/tftp 为默认tftp目录)

#修改如下文件
tftp dgram udp wait nobody /usr/sbin/tcpd /usr/sbin/in.tftpd /tftproot

3.sudo mkdir /tftproot

4.sudo chmod 777 /tftproot

5.sudo /etc/init.d/openbsd-inetd restart

6.查看69端口是否有打开 ：netstat -an | more | grep udp

udp 0 0 0.0.0.0:69 0.0.0.0:*

7.本机测试：

      a. 在/tftproot 下新建文件1.txt   
      b. 在其他目录下测试：

       tftp 127.0.0.1
       tftp> get 1.txt
        Received 12 bytes in 0.0 seconds
        tftp> quit

the way to start dhcpd:

1 apt-get install isc-dhcp-server
2 /etc/dhcp/dhcpd.conf
host horse-i104-eth0 {
  hardware ethernet 00:80:64:c5:29:f3;
  next-server 10.151.121.163; #the IP of tftp server, can be same one with dhcp server
  #next-server 10.151.120.5;
  filename "I10_pxe";
  fixed-address 10.151.121.56;
}
service isc-dhcp-server start