In the Control Panel, click "Programs and Features", then click on "Turn Windows Features On or Off" in the upper left-hand corner. From the Windows Features list that appears, locate and check "Telnet Client".
From here, go ahead and click OK and wait for the new service to provision. Once it's finished, go ahead and close out of all Control Panel windows.
Now that Telnet is configured, let's get into our device. I will assume a few preconditions before moving forward:
With PuTTY open, select the Telnet connection type, then type in the IP address, and also change the port from 23 to 2002. Conventionally, Telnet uses port 23 by default, but our devices use port 2002 by default for Telnet.
And that's it! We've successfuly connected to our device using Telnet. If you're not using PuTTY to connect to the RTU and instead are using the Telnet command, the process is relatively easy. Enter the command below:
telnet <IP_ADDRESS> 2002
In the same Telnet window that we have open, we can also Telnet into another device. This is practical if you have a direct line to one NetGuardian, but other devices behind it are either on a different subnet, or belong on their own network entirely.
From the current window, type "T" for Telnet, then enter just the IP address of another device on the same subnet as the current NetGuardian, and finally enter the port number when prompted. A connection will be established to the RTU, verifying both connectivity over port 2002 and also connection over IP.
You can see from the picture above that we have first logged in to one RTU, then logged into another RTU through that connection. While this is not ideally what you will see out in the field, this is a great way of verifying port availability, as well as being able to remotely configure a device that may be on a different network, effectively using the host NetGuardian as a static route.
Telnet is a great tool that allows us to use the same Craft interface from a distance. It is useful when the Craft cable may not be long enough, or your office is a ways away. Either way, we hope this article has equipped you with an understanding of how Telnet works and how our devices utilize it.
If you have any further questions on setup or are encountering other issues, give us a call and our expert tech support would be more than happy to assist in any way we can.