First, I'd like to say that this is a great discussion and an important one at that so thank you Jeremy for starting it.
It's funny that I'm just stumbling on this thread because this week I am training a junior network admin and I ran into a situation like this. I was showing him some of the features and bells/whistles of Putty when he asked me to give him my Putty list for all of our network devices. I could have taken the easy road and quickly exported the registry key for the saved sessions but I thought better of it. I wanted him to know the network more intimately than someone telling him what IP address to log into; he needed context. So I had him do an exercise that I've used in the past on another coworker that I trained in the past. I had him start with a blank state. I told him the only thing he could use was Windows in order to start mapping the network. Right away, he gave me a deer-eyed look and after a few minutes, he came back to me not knowing where to begin. So I decided to give him a hint. I told him that the Windows command prompt was his friend and also asked how he would get out to the rest of the network, including the Internet. Immediately, I saw the light bulb come on and he quickly went back to his desk to run the "ipconfig" command find out what his default gateway was. From there, he used Putty to try and gain access to whatever device had that IP address. What do you know.... Success! He now had his first switch mapped and saved in Putty, however, he was stuck again. I then instructed him to look for layer 2 connections first by using "show cdp neighbors". In this case, there were no CDP neighbors because of the nature of our network and the fact that it was the L3 device/gateway for the building. So "where do I go from here" is what he most likely thought... I could see the wheel turning at an incredible pace but I could tell nothing was coming to him so I decided again to give him a break. I told him when he reaches the end of a device's CDP neighbors list which will give you L2 adjacent connections, try using "show ip eigrp neighbors" to give him the L3 connections. Even if L2 isn't adjacent as is the case on our network, there are still L3 adjacencies that he can use to his advantage. Hurrying back to his desk, he performed the command and voila, he found ONE lone neighbor- an olive branch if you will. This brought him to the Core of our network, where all of our buildings are terminated and a honey pot of information. From there he was set, constantly finding new devices and rabbit holes to go down. He was learning the network and he didn't even realize it.
After some time had passed, I went over to his desk and saw a notepad where he was drawing a hierarchical drawing of how the devices were connected. He began to map the network even without me having to ask. He realized that it helped him to physically draw it out so that he could get a visual picture of the network. Was this the most efficient way of learning the network? No. Are there more things he can do or tools he can use to further learn and map the network? Sure. But for someone who has little to no experience on the command-line and no practical experience, this was plenty for now and he is well on his way to understanding the network. In addition, some of the questions he posed while performing this exercise provided him the opportunity to learn more complicated ideas where an explanation was needed while also reenforcing my knowledge of the network.
Oh! And that context I wanted him to have when someone says, "Hey, log into <IP address> for me."; he has that now.
Regards,
Keith
