Linux commands for opening and closing ports

This article mainly introduces the command of Linux open port and close port in detail, the sample code in this article is very detailed, it has certain reference value, interested friends can refer to it.

How do I close the linux port?

The method of opening and closing ports in Linux

First, check which ports are opened netstat-anp

2. Close the port number:

Iptables-An OUTPUT-p tcp-- dport port number-j DROP

Third, hit the slogan of the beginning:

Iptables-An INPUT-ptcp-- dport port number-j ACCEPT

Save settings

Service iptables save

5. The following is how to use the linux open port command.

Nc-lp 23 & (Open port 23, that is, telnet) netstat-an | grep 23 (check whether port 23 is open)

6. Linux Open Port Command every open port requires a corresponding listener

After reading the contents of the appeal, do you have a general understanding of Linux's orders to open and close ports? If you want to know more, welcome to follow the industry information channel!