telnet or console

BennyTheMan

In my studying for CCENT 1, I constantly run across the questions related to "telnetting" or "consoling" into a switch or router. Can someone give me an idea of what these actually mean. I use packet tracer and do the configurations in the command line and now that I think about it there is no monitor on the actual routers and switches, so I'm not sure if packet tracer is consoling or telnetting..

Any explanations greatly appreciated,

Thanks,

-Benny

Rocket Impossible

Packet Tracer is emulating being consoled into a piece of hardware via a console cable and a terminal emulator, like Putty. Download Putty and check it out. One of the benefits of having at least one piece of gear is being able to see and learn how you actually access a switch or router. "Telnetting" looks very similar to "consoling" only you are accessing the hardware via the telnet protocol by IP address.

bettsy584

If your new to networking, forget Telnet is a thing. It's crap as everything is sent in clear text. You should always be using SSH if you are connecting remote sessions to networking devices.

The thing to remember is that Consoling (using the serial interface on a laptop to the console port on a switch/router) is really only for out of band management, and the initial setup of a device.

You will use SSH for your day to day management of a device. SSH is fully encrypted not like Telnet.

liz4rd

You need to console in, which is a direct connection from your PC into the device, because you have no ip to remote to. Then you can put an IP on it, which makes it available to connect to by telnet/ssh, which is remote and doesn't need a physical connection.

rob42

Maybe the explanations already given answer your questions, or maybe not, but I offer the following for you…

To log into and configure a device such as a Cisco Router, one needs to be able to use the command line interface that is part of the IOS (you probably know this already). With a Router that has not been configured, you can’t log into it via a TCP/IP network using either a SSH or Telnet client, rather you need to connect to it directly using the console connection port and a console connection cable, pictured.



Not all modern computers have the requisite RS232 9-pin D socket and I don’t know if the USB-to-RS232 converters work as I've never used one (I’m sure that someone here will know).

The RS232 connection on your computer is usually called COM1 and older computers may have a COM2, etc, but the sockets should be labelled.

After the device has been configured to connect to a TCP/IP network, one can use either a Telnet or SSH client to access the CLI. As already stated, the Telnet protocol is not secure so all the data sent and received is in clear text. This is fine for a privet network, but not for a public network. For a public network an SSH client is needed.

If you’re not familiar with “SSHing” into a server or any other device, I’d suggest you learn. It’s a very useful skill to have.

I use a Raspberry PI as a file/print/HTTP server and setting this device up over a local network, using a SSH client has taught me a good deal.

This information is to the best of my knowledge and I stand to be corrected on any points. In fact, I’d welcome any corrections as this would improve my knowledge.

I hope this is of help.

NetworkNewb

rob42 wrote: »

Not all modern computers have the requisite RS232 9-pin D socket and I don’t know if the USB-to-RS232 converters work as I've never used one (I’m sure that someone here will know).

Yep, they work good. When I studied for my CCENT (haven't completed my CCNA yet), I got a bunch of them and hooked up all my switches and routers to a USB hub with those and plugged the hub into my computer. That way I was consoled to each of them all the time.

rob42

NetworkNewb wrote: »

Yep, they work good. When I studied for my CCENT (haven't completed my CCNA yet), I got a bunch of them and hooked up all my switches and routers to a USB hub with those and plugged the hub into my computer. That way I was consoled to each of them all the time.

Good to know; cheers man. Is there some sort of configuration part of the driver so that you can define COM1, COM2 etc?

NetworkNewb

Each port on the hub just shows up as COM1, COM2, etc on their own. No setup/config needed. I honestly didn't know it would do that or not when I first set it up, being its all just being plugged in the same port on my computer. But worked pretty slick.