iptables规则的删除

iptables -L INPUT --line-numbers  列出INPUT 链所有的规则
num  target    prot opt source              destination        
1    REJECT    tcp  --  anywhere            anywhere            tcp dpt:microsoft-ds reject-with icmp-port-unreachable 
2    REJECT    tcp  --  anywhere            anywhere            tcp dpt:135 reject-with icmp-port-unreachable 

...
...
    删除指定的第2行规则：
iptables -D INPUT 2