LINUX Checks whether the port is occupied

I have never been able to figure out whether the port is occupied. After asking many people, I finally figured it out. Now let me summarize:

1.netstat -anp |grep port number

As follows, I take 3306 as an example, netstat -anp |grep 3306 (note here, I am operating as a normal user, so I added sudo. If you are operating as a root user, you can view it without adding sudo), as shown in Figure 1:

Figure 1

In Figure 1, the monitoring status is LISTEN, which means it is occupied. The last column shows that it is occupied by the service mysqld. Check the specific port number. As long as there is a line like the one in the figure, it means it is occupied.

2.netstat -nultp (no need to add port number here)

This command is used to view all currently used ports, as shown in Figure 2:

Figure 2

As you can see from the picture, my port 82 is not occupied.

3.netstat -anp |grep 82 to check the usage of port 82, as shown in Figure 3:

Figure 3

It can be seen that there is no LISTEN line, so it means that it is not occupied. Note that the LISTENING in the figure does not mean that the port is occupied. Do not confuse it with LISTEN. When checking the specific port, you must see the line of tcp, port number, and LISTEN to indicate that the port is occupied.

The above is the full content of this article. I hope it will be helpful for everyone’s study. I also hope that everyone will support 123WORDPRESS.COM.