iptables常用操作

1.查看防火墙

#默认是filter表
[root@m01 ~]# iptables -nL
Chain INPUT (policy ACCEPT)
target     prot opt source               destination         
ACCEPT     all  --  0.0.0.0/0            0.0.0.0/0            state RELATED,ESTABLISHED
ACCEPT     icmp --  0.0.0.0/0            0.0.0.0/0           
ACCEPT     all  --  0.0.0.0/0            0.0.0.0/0           
ACCEPT     tcp  --  0.0.0.0/0            0.0.0.0/0            state NEW tcp dpt:22
REJECT     all  --  0.0.0.0/0            0.0.0.0/0            reject-with icmp-host-prohibited

Chain FORWARD (policy ACCEPT)
target     prot opt source               destination         
REJECT     all  --  0.0.0.0/0            0.0.0.0/0            reject-with icmp-host-prohibited

Chain OUTPUT (policy ACCEPT)
target     prot opt source               destination

2.查看指定表

#-t:    指定表
[root@m01 ~]# iptables -nL -t nat

3.清除防火墙规则

[root@m01 ~]# iptables -F
[root@m01 ~]# iptables -X
[root@m01 ~]# iptables -Z

4.添加防火墙规则

[root@m01 ~]# iptables -t filter -A INPUT -p tcp --dport 22 -j DROP

[root@m01 ~]# iptables -nL
Chain INPUT (policy ACCEPT)
target     prot opt source               destination         
DROP       tcp  --  0.0.0.0/0            0.0.0.0/0            tcp dpt:22

5.删除防火墙规则

#防火墙规则加序号
[root@m01 ~]# iptables -nL --line-numbers
Chain INPUT (policy ACCEPT)
num  target     prot opt source               destination         
1    DROP       tcp  --  0.0.0.0/0            0.0.0.0/0            tcp dpt:2
2    DROP       tcp  --  0.0.0.0/0            0.0.0.0/0            tcp dpt:22

Chain FORWARD (policy ACCEPT)
num  target     prot opt source               destination         

Chain OUTPUT (policy ACCEPT)
num  target     prot opt source               destination

#删除指定id的规则
[root@m01 ~]# iptables -D INPUT 3