2019 - Proper rack case
While open-air "case" can work, it's not a good idea to leave all the electronics exposed to elements. Sometime during the year, Newegg had a flash sale on a Rosewill L4000 4U server case for cheap, and so I upgraded the lab once more.
The components largely remind the same as before, just in a proper case now.
After discover the r/homelabsales subreddit, I was able to score a good deal on a Cisco switch, thinking it will help me studying for the CCNA in the future. This switch is the SG200-52P, which is a huge upgrade over the previous 16-Port Netgear switch, in terms of both functionality and more ports.
But server racks are still out of the question, due to both cost and lack of space. Janky mounting it is.