Comment by gerdesj

Good skills - you are well on the way to Engineer with a capital E.

You cannot see network traffic.

You'd be amazed at how many people think they can diagnose a network fault without using tools like this. Everyone is an expert until they prove themselves to be a bit of a twit!

At layer 1 you have electrical issues to deal with and that will need some hardware. Obviously you need to pick your network model too. Here you'll go in with a couple of PCs/laptops and APIPA and/or a Fluke or a cheap network tester effort off of Amazon. Use what you have available.

After that you will need nmap and wireshark. LLDP and CDP are very handy too.

If you have to deal with a large network, I can highly recommend Netdisco.