In Linux, the iptables firewall releases the port to reject the port and view the opened port.

In Linux, the iptables firewall releases the port to reject the port and view the opened port.

I use fedora 14.

1. view the port enabled by iptables firewall:/etc/init. d/iptables status

[Root @ hzswtb2-mpc ~] #/Etc/rc. d/init. d/iptables status or service iptables status
Table: filter
Chain INPUT (policy ACCEPT)
Num target prot opt source destination
1 ACCEPT tcp -- 0.0.0.0/0 0.0.0.0/0 tcp dpt: 3306

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

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

 

2. Enable tcp port 8080

/Sbin/iptables-I INPUT-p tcp -- dport 8080-j ACCEPT

/Etc/rc. d/init. d/iptables save or service iptables save # save the configuration/etc/rc. d/init. d/iptables restart or service iptables restart # restart the service

[Root @ hzswtb2-mpc ~] #/Sbin/iptables-I INPUT-p tcp -- dport 8080-j ACCEPT
[Root @ hzswtb2-mpc ~] #/Etc/rc. d/init. d/iptables save
Iptables: Saving firewall rules to/etc/sysconfig/iptables: [OK]
[Root @ hzswtb2-mpc ~] #/Etc/rc. d/init. d/iptables restart
Iptables: Flushing firewall rules: [OK]
Iptables: Setting chains to policy ACCEPT: filter [OK]
Iptables: Unloading modules: [OK]
Iptables: Applying firewall rules: [OK]

[Root @ hzswtb2-mpc ~] # Service iptables status
Table: filter
Chain INPUT (policy ACCEPT)
Num target prot opt source destination
1 ACCEPT tcp -- 0.0.0.0/0 0.0.0.0/0 tcp dpt: 8080
2 ACCEPT tcp -- 0.0.0.0/0 0.0.0.0/0 tcp dpt: 3306

3. Delete chain INPUT and specify Rule 1;

[Root @ hzswtb2-mpc ~] # Iptables-d input 1
[Root @ hzswtb2-mpc ~] # Service iptables status
Table: filter
Chain INPUT (policy ACCEPT)
Num target prot opt source destination
1 ACCEPT tcp -- 0.0.0.0/0 0.0.0.0/0 tcp dpt: 3306

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

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

4. Reject specifies the port;

[Root @ hzswtb2-mpc ~] #/Sbin/iptables-I INPUT-p tcp -- dport 8080-j REJECT
[Root @ hzswtb2-mpc ~] # Service iptables status
Table: filter
Chain INPUT (policy ACCEPT)
Num target prot opt source destination
1 REJECT tcp -- 0.0.0.0/0 0.0.0.0/0 tcp dpt: 8080 reject-with icmp-port-unreachable
2 ACCEPT tcp -- 0.0.0.0/0 0.0.0.0/0 tcp dpt: 3306

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

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