Telnet command mode operation instructions (1)

We have previously introduced the use of the Telnet protocol. I'm sure you have some knowledge about its working model and process. Here, we will explain the content about the Telnet command mode. I hope you can understand how Telnet commands are performed.

Telnet command mode

In addition to Telnet, remote logon is easy to learn. Telnet also has many features. in Telnet command mode, any character except "escape" can be sent to the remote host. because the "escape" character is a special command mode of the client in Telnet, its default value is "Ctrl-]". but be sure not to confuse it with the Esc key on the keyboard. We can set "escape" to any character, but it is impossible for Telnet to transmit this character to the remote host, the Esc key is a non-printable character. Telnet uses it to delete commands in the remote system. remember that the "escape" character is not always expressed as "Ctrl.

You can simply type Telnet without the machine words. In this case, Telnet> is displayed. This means that the Telnet command mode is waiting for the command to be typed, such as entering the question mark "? "A useful command table is obtained:

 
 

  
  
telnet: ?  
  
  
Commands may be abbreviated, Command are:  
  
  
open connect to a site  
  
  
close close currect connection  
  
  
quit exit telnet  
  
  
display display operating parameters  
  
  
send transmit special characters ('send ?' for more)  
  
  
set set operating parameters('set ?' for more)  
  
  
status print status information  
  
  
toggle toggle operating parameters('toggle ?' for more)  
  
  
mode try to enter line-by-line or character-at-a-time mode  
  
  
? print help information 
 
 

Although there are many commands and even sub-commands, only some of them are commonly used. Here are some of the following:

Close:

This command terminates the connection. it can automatically disconnect from the remote system, or use it to exit Telnet. This command can be used if you want to quit when you enter a network host.

Open:

It is used to connect to a named machine, and the name or IP address of the target machine must be given. if no machine name is provided, select a machine name in Telnet command mode. note that you should use "close" to close any existing connection before using the "Open" command.

Set ECHO:

The local response is On or Off. whether to display the output content on the screen. basically the same as dos echo. if the machine is in echo on and you want to change it to OFF, You can input set echo and change it back to echo off. Then you can type set echo. (This is short. If you have any questions, contact me)

Set escape char:

Create a "escape" character to a special symbol. to replace it with a certain control symbol, you can use "asis" or enter the symbol "^" and add the letter B (for example: ^ B ). during normal operation, the character "escape" is not required, and the symbol used as "escape" cannot be used again. this is similar to setting the true meaning of each key on the keyboard in many programs. however, if you are running a daisy-chained application system, it is useful to re-determine the features of the "escape" character. for example, use Telnet from system A to system B, and then use Telnet to register and enter system C. if a fault occurs when the system is working on system C, when the "escape" symbol is the same, the connection between system B and system C cannot be interrupted. enter the "escape" identifier, which will always be in the command mode of system. if different "escape" symbols are used in each Telnet part, you can select one of the command modes by typing an appropriate symbol, this can also be used for terminal simulation in other applications ).

Quit:

Use it to smoothly launch the Telnet program.

Z:

The Telnet command mode is retained, but other commands are temporarily returned to the local system for execution. connections and other options in Telnet are retained when Telnet is restored.

Carriage Return:

Returns a command from the command mode to the connected remote machine. in addition, there are many other commands that can launch the command mode. the following example shows how to enter porky.math.ukans.edu from registration, enter the command mode, and return porky ::