Telnet-Test port number

2. Click on the computer's Start menu-run, enter the cmd command, and then OK. Open the cmd command line.

4. Enter Telnet test port command: Telnet IP port or Telnet domain port

   Enter

6. If the port is closed or unable to connect, display a link that cannot be opened to the host, and the link fails

8. When the port is open, the link succeeds, then it goes to the Telnet page (All Black), proving that the port is available

9. The Telnet client commands a common command:

   Open: Use Openhostname to establish a Telnet connection to the host.

   Close: Use the command Close command to close an existing Telnet connection.

   Display: Use the display command to view the current settings of the Telnet client.

   Send: Use the Send command to send commands to the Telnet server. The following commands are supported:

   AO: Discards the output command.

   Ayt: "Is You There" command.

   ESC: Sends the current escape character.

   IP: Interrupt process command.

   Synch: Performs a Telnet synchronization operation.

   BRK: Sends a signal.

   Commands other than those listed in the previous table are sent as strings to the Telnet server. For example, SENDABCD will send the string ABCD to the Telnet server, so that the string will appear in the Telnet session window.

   Quit

   Use the QUIT command to exit the Telnet client.

   telnet Configuration and Telnet usage

   When you build or configure a network environment, you often use the ping command to check whether the network is up or down. In some cases, the ping command is not available, such as firewall prohibitions or access policy restrictions. You can use Telnet to test the map port or the remote access host.

   The Telnet protocol is one of the TCP/IP protocol families, the standard protocol and the main way of Internet remote Login service, and is often used for remote control of Web server, which can be used by the user to run the remote host on the local host.

   Below is a stream to share:

   1. How do I configure Telnet on a Windows environment? (resolves: "Telnet is not an internal or external command" issue)

   (1) Configure Telnet on the WIN7&WIN8 system.

   (2) Configure Telnet on the Windows Server 2008 Server System.

   2. How to use Telnet test port?

   (1) Telnet IP port.

   (2) Telnet domain port.

   3. How do I remotely access other hosts using Telnet?

   Tools/Materials
   • Telnet Server and Telnet client.
   • Two PCs, using a virtual machine is also available.
   • For Windows systems its Win7, WIN8, and Windows Server R2.
   Method/Step
   • 1.1. Configure the Telnet service on the WIN7&WIN8 system.

     Add Telnet service on 1.1.1, Win7.

     Operation Process: Click "Start" → "controller Panel" → "View by: Type" then click on "Program" ("View by: Large Icon" then click "Programs and Features") → "Turn Windows features on or off" → check Telnet server and client in the "Windows features" screen → last Click OK to wait for the installation.

   • Configure Telnet on 1.1.2, Win7 to automatically and turn on the service.

     (1) Right click on "Computer" → click "manage" → expand "services and Applications" → Click on "Services" → Right click "Telnet Service" in its menu bar click on "Properties" → "Startup type" set to "automatic" → Click "OK" to complete the startup type setting.

     (2) Right-click the Telnet service again and click "Start" in its menu bar to complete the Telnet service startup.

   • 1.1.3, verify that the Telnet service is successfully installed and started.

     (1) at the command prompt, enter: Telnet-help, which appears to resolve "Telnet is not an internal or external command."

     (2) at the command prompt, enter: Telnet 127.0.0.1, which appears as if the Telnet service started successfully.

   • 1.2. Configure the Telnet service on the Windows Server R2 system.

     1.2.1, enter the Server Manager interface for Windows Server.

     Procedure: Right-click on the desktop computer → Click on "manage" → go to "Server Manager" interface.

     or through "start" → "controller Panel" → "View by: Type" then click on "Program" ("View by: Large Icon" then click "Programs and Features") → "Turn Windows programs on or off" → Go to the "Server Manager" interface.

   • 1.2.2, add the Telnet service on the Windows Server System.

     Operation process: Click "Functions" → "add features" → tick Telnet server and client → "Next" → "Install" → wait for the installation to finish and click "Close" to complete the Telnet service Add.

   • Configure Telnet on 1.2.3, Windows Server System to automatic and start the service.

     Operation Process:

     (1) In the Server Manager interface Click "Configuration" → "Services" → Right click "Telnet Service" in its menu bar click on "Properties" → "Startup Type" is set to "automatic" → Click "OK" to complete the startup type setting.

     (2) Right-click the Telnet service again and click "Start" in its menu bar to complete the Telnet service startup.

   • 1.2.4, verify that the Telnet service is turned on.

     At the command prompt, enter: Telnet 127.0.0.1, which appears as if the Telnet service started successfully.

   • 2. Use Telnet to test the port.

     2.1, Telnet IP port, (firewall to do the corresponding restrictions).

     (1) If the test host: Telnet 127.0.0.1 80 or 23, the result shows that its 80 port is not available, 23 port on is available.

     (2) If the other host: Telnet 10.0.0.27 80 or 21, the result shows that its 80 port is not available, 21 port on is available.

     Note: 10.0.0.27 host is the other host I used to do the test.

     Telnet IP Port display: Connection failure is a port that is not available or is forbidden.

     if the Telnet IP port is available, it will enter an interface, the interface is different depending on the port.

   • 2.2. telnet domain port.

     Take "Baidu" for example, 21 is the FTP service port generally does not turn on, and 80 is the HTTP port therefore certainly opens.

   • 3. Use Telnet to access a host remotely.

     Background: If the remote access host using Telnet protocol, its access host and the access host must install the appropriate Telnet service, the access host needs to add a user in the user group as a member of the Telnetclinets group, its access host input user name and password to access the host.

     3.1. Add a user to the TelnetClients group on the accessed host.

     Operation Process: Right-click the desktop "computer" → "Management" → "System tools-Local Users and groups-users" → Right click on the user in its menu bar click on "Properties" → "Member of-add" → "Enter the object name to select (example)" Enter "telnetclients" → finally "OK".

   • 3.2. Ping the IP of the host to detect if the network is normal. such as: Ping 10.0.0.31.

   • 3.3. When the network is normal, Telnet IP initiates the remote access host.

     Input: Telnet 10.0.0.31 hit enter;

     Enter the Telnet client interface and ask "Do you want to send (y/n):" Enter Y to hit enter;

     Enter the Telnet service interface, enter (the access host) Username and password to hit enter;

     Finally enter the command prompt directory of the host being accessed, that is, the Telnet remote access host was successfully used.

Telnet-Test port number