3Com 10014299 manual Force shut down Telnet Process, Example of Telnet, Display and Debug

Terminal Service of Telnet Connection 65

The interface listen port number is within the range of 1025 to 65535. Please note that the listen port number cannot be the same as that of the widely used ports. By default, the port number and asynchronous interface have the following relations:

■The async serial interface number starts from 2001. For instance, the first async serial interface number is 2001, the second is 2002, and so on.

■The AUX interface number is 3000.

■The sync serial interface number starts from 3001. For instance, the first sync serial interface number is 3001, the second is 3002, and so on.

Force shut down Telnet Process

In some cases (such as usage of Telnet by a malicious user), the administrator user logging from the Console port can use the kill telnet command to disconnect the link from the Telnet user to the router or disconnect the link according to the process number found through the display client command. Use caution when executing this command.

Please perform the following configuration in system view.

Table 48 Force to shut down Telnet process

Operation	Command
Force to shut down Telnet process	kill telnet { all userID userid }

Display and Debug	Perform the following configuration in all views.
Reverse Telnet	Table 49 Establish Telnet Server or Telnet Client connection
Connection
		Operation	Command
		Display information of Telnet clients	display client
		Display information of Telnet connection	display tcp status

Typical Configuration

Example of Telnet and

Reverse Telnet

display client can only be used to display the interface through which the Telnet client connected to the router passes. If you want to view the IP address of the Telnet server connected to the router, you should execute the display tcp status command. The TCP connection whose local port number is 23 is the Telnet connection, including the Telnet client connection and Telnet server connection.

Example of Telnet

In the networking diagram shown in Figure 28 “Telnet server service”, the host establishes connection with router A (IP address 10.110.0.1), then logs on and configures router B (IP address 129.102.0.1).

1Execute the following commands on the user host and Telnet to Router A.

C:\WINDOWS>Telnet 10.110.0.1

2Execute the following commands in the popup Telnet window, and log onto Router B.

[RouterA]telnet 129.102.0.1

Trying 129.102.0.1 ...(use CTRL + C to break)

Connected to 129.102.0.1

Service port is 23 .

Username:guest