I am working in a small business, but the office is quite large. For ages, everything ran over Wi-Fi here, but it's simply not reliable enough (Walls blocking signal, high latency, etc).
Some days ago I started wiring LAN cables to everywhere in the office. Starting on the "main" TP-Link 16 port switch, I pushed longer LAN cables to certain places that are further away, and on certain points where more than 1 PC is, I bought TP-Link Switches (5 ports) and then plugged all those PCs to that switch.
Until then, I thought it was all fun and games, but testing the cables I noticed that I have no connectivity whatsoever. It seems that I cannot plug two switches together, because doing that does not allow traffic going through.
Strange enough, when I connect them together over a short distance, it works. I'm using a Cat5e cable (It doesn't have any shielding, just twisted pairs). Cat5e cables are made to work up to 100 meters. The LAN cables here are only about 20-30 Meters. Interference isn't likely the cause, because the cables don't run near electricity (only a very short distance, and there isn't even something pushing AC through. It's a wall socket - unused.)
With some searching I saw that "like" devices (same type) should be wired together with a crossover cable. I've done that and connectivity still doesn't work.
The cables are wired following way on both sides (If that matters):
Any help is greatly appreciated.
Picture of the working network below: