udhcpd配置及使用

基于mips芯片qca953x平台；

今天测试板子wifi无线连接的时候，手机端怎么也连接不上，连上wifi后手机端立即就闪断了，后面发现原因是无线路由开发板没有开启dhcp服务器，手机端获取不到ip地址，下面来讲下busybox的dhcp服务器udhcpd的使用及配置。

1.使用原始的udhcpd配置文件/etc/udhcpd.conf启动dhcp服务器udhcpd，结果出现以下错误

~ # udhcpd /etc/udhcpd.conf  &
info, udhcpd (v0.9.9-pre) started
error, max_leases value (254) not sane, setting to 234 instead
error, Unable to open /var/lib/misc/udhcpd.leases for reading
error, SIOCGIFADDR failed, is the interface up and configured?: No such device

原始的/etc/udhcpd.conf文件内容，部分省略，省略部分采用原来的默认配置：

# Sample udhcpd configuration file (/etc/udhcpd.conf)

# The start and end of the IP lease block

start 192.168.1.20 #default: 192.168.0.20
end 192.168.1.254 #default: 192.168.0.254

# The interface that udhcpd will use

interface ixp0 #default: eth0

# The maximim number of leases (includes addressesd reserved
# by OFFER's, DECLINE's, and ARP conficts

#max_leases 254 #default: 254

修改后的/etc/udhcpd.conf文件内容，部分省略，省略部分采用原来的默认配置：

# Sample udhcpd configuration file (/etc/udhcpd.conf)

# The start and end of the IP lease block

start 192.168.1.20 #default: 192.168.0.20
end 192.168.1.254 #default: 192.168.0.254

# The interface that udhcpd will use
interface br0  #default: eth0 --- 解决error, SIOCGIFADDR failed, is the interface up and configured?: No such device

# The maximim number of leases (includes addressesd reserved
# by OFFER's, DECLINE's, and ARP conficts
max_leases 234 #default: 254  --- 解决error, max_leases value (254) not sane, setting to 234 instead

解决error, Unable to open /var/lib/misc/udhcpd.leases for reading，在板子上执行以下命令：

 # mkdir -p /var/lib/misc/             
 # touch /var/lib/misc/udhcpd.leases

2.再次启动udhcpd进程

# udhcpd /etc/udhcpd.conf &

然后手机重连板子的wifi，手机获取到ip地址后，wifi无线连接成功。