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交叉编译器：arm-linux-gcc-4.5.4
Linux内核版本：Linux-3.0
开发板：FL2440
本文章的内核已经已经添加了DM9000的网卡，USB驱动，使用的是initramfs的文件系统。
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一、配置内核
[*] Networking support --->
Networking options --->
<*> Packet socket
<*> Unix domain sockets
[*] TCP/IP networking
[*] IP: kernel level autoconfiguration
[*] IP: DHCP support
[*] Network packet filtering framework (Netfilter) --->
二、配置busybox
[*]udhcp server(udhcpd)
[*]udhcp client(udhcpc) 都选上 udhcpd就是终端设备作为DHCP服务器 ；udhcpc就是终端设备作为DHCP客户端
Networking Utilities --->
[*] udhcp client for DHCPv6 (udhcpc6)
[*] udhcp server (udhcpd) //生成udhcpc命令
sudo make install
从Busybox的examples/udhcp/下拷贝simple.script文件到开发板的/usr/share/udhcpc/下，并重命名为default.script，然后更改文件default.script的权限为可执行文件。
三、测试
>: mv simple.script default.script
>: chmod a+x default.script
>: mkdir -p /usr/share/udhcpc
>: cp default.script /usr/share/udhcpc/
>: ping 192.168.199.1
PING 192.168.199.1 (192.168.199.1): 56 data bytes
64 bytes from 192.168.199.1: seq=0 ttl=64 time=50.549 ms
64 bytes from 192.168.199.1: seq=1 ttl=64 time=47.244 ms
--- 192.168.199.1 ping statistics ---
2 packets transmitted, 2 packets received, 0% packet loss
round-trip min/avg/max = 47.244/48.896/50.549 ms
>: udhcpc -i wlan0
udhcpc (v1.20.2) started
Setting IP address 0.0.0.0 on wlan0
Sending discover...
Sending select for 192.168.199.181...
Lease of 192.168.199.181 obtained, lease time 43200
Setting IP address 192.168.199.181 on wlan0
Deleting routers
route: SIOCDELRT: No such process
Adding router 192.168.199.1
Recreating /etc/resolv.conf
Adding DNS server 192.168.199.1
>: ifconfig
eth0 Link encap:Ethernet HWaddr D6:10:9A:CD:CD:91
inet addr:192.168.1.111 Bcast:192.168.1.255 Mask:255.255.255.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:248 errors:0 dropped:0 overruns:0 frame:0
TX packets:12 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:23616 (23.0 KiB) TX bytes:786 (786.0 B)
Interrupt:51 Base address:0x4300
wlan0 Link encap:Ethernet HWaddr 00:A1:B0:40:6F:9A
inet addr:192.168.199.181 Bcast:192.168.199.255 Mask:255.255.255.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:1635 errors:0 dropped:431 overruns:0 frame:0
TX packets:39 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:150647 (147.1 KiB) TX bytes:4231 (4.1 KiB)
>: route
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
default Hiwifi.lan 0.0.0.0 UG 0 0 0 wlan0
192.168.1.0 * 255.255.255.0 U 0 0 0 eth0
192.168.199.0 * 255.255.255.0 U 0 0 0 wlan0