Iptables怎么打开端口！

shirely

财务要通过网上申报，需要把防火墙（IPTABLES)的7001或7002端口打开，我试用“IPTABLES -A INPUT -t 7001 -j accept”系统提示"can't initialize iptables table '7001'":table does not exit(do you need to insmod)
perphas iptables or your kernel needs to upgraded
请问怎么解决？我对LUNIX系统和iptables防火墙不熟悉，请各位帮帮我！