如果执行 iptable -L 出现以下信息，那么就需要重新配置和编译内核：
iptables v1.4.2: can’t initialize iptables table `filter’: Table does not exist (do you need to insmod?)
Perhaps iptables or your kernel needs to be upgraded.
内核配置选项：
Networking —->
Networking options —->
[*] Network packet filtering (replaces ipchains) —>
Core Netfilter Configuration —>
<*> Netfilter Xtables support (required for ip_tables)
IP: Netfilter Configuration —>
<*> Connection tracking (required for masq/NAT)
<*> IP tables support (required for filtering/masq/NAT)
<*> IP range match support
<*> Packet filtering
<*> REJECT target support
<*> Full NAT
/home/mysytem/chipcorekernel/linux/kernels/mips-linux-2.6.15
/home/mysytem/chipcorekernel/linux/kernels/mips-linux-2.6.15/arch/mips/configs/pb44-small_defconfig’