Use telnet commands to improve the security level of remote Logon

In the telnet command application, we can use some port changes to ensure its security. Because the telnet security issue deserves our attention. Now let's take a look at the specific operation methods. Hope to help you.

The telnet command is the default remote logon program in the Windows Server 2008 Server system, because the program is directly integrated into the Server system and easy to use, therefore, network administrators often use this program when managing servers. however, when using telnet commands to remotely control the server system, the control information is usually transmitted in plaintext over the network, some malicious attackers can easily intercept control information such as the account name and password, and the identity authentication method of the telnet program also has obvious weaknesses, that is, it is particularly vulnerable to attacks by others.

When telnet commands remotely control the Windows Server 2008 Server system, the default network port "23" is automatically used, and almost everyone is familiar with this port, to protect the security of telnet remote connection, we only need to modify the default network port number of the program as follows to prevent others from using the telnet command to remotely control the server system:

First, on the Windows Server 2008 Server system desktop, click the "Start"/"run" command. In the displayed system running text box, enter the "cmd" string command and click the Enter key, open the doscommand line work window of the corresponding system;

Then, at the command line prompt in the DOS window, enter the string command "tlntadmn config port = 2991" (where "2991" is the new port number after modification ), to prevent conflict between the newly set network port number and the existing system port number, we must make sure that the new port number entered here cannot be set to a known system service port number;

After confirming that the preceding string command is entered correctly, click the Enter key. The port number used by the telnet command will automatically become "2991". At this time, the network administrator must know the new port number, in order to use this program to remotely control the Windows Server 2008 Server system.

Of course, we can remotely modify the telnet program Port Number of the Windows Server 2008 Server system without going to the Server site. We only need to open the doscommand line work window in the local client system, enter the string command "tlntadmn config \ server port = 2991-u xxx-p yyy" (Server indicates the host name or IP address of the remote server system, port = 2991 indicates the remote login port number to be modified. xxx indicates the username used to log on to the server system. yyy indicates the password of the corresponding user account. After you click the Enter key, the telnet port number of the remote server system is 2991.