How to detect a network break without breaking the wall?

Question

Cables and wires

Good afternoon. In the office, eth ports suddenly stopped working, beautifully recessed into the wall of the office. There is a common wall of two cabinets, it has two pairs of sockets (4 ports in total), they are almost mirror-like. Worked, worked and stopped. There is no link in any of the four ports, the Lanmaster tester showed a short circuit at a distance of about 2.5 meters from the sockets (30-40 meters to the server room with patch panels). The walls and ceilings are nice and solid, no hatches or armstrongs to peek into. There is no network map, the office has just come out from under the crooked outsourcing. I suspect that somewhere deep in the wall there is a hub \ twist \ scotch locks, with which something bad happened. How close is my thought to the truth? And is it possible to somehow verify this without breaking the wall and ceiling? Without an endoscope? And most importantly: how to fix it,

Answer 1

Buy a NetFluke for 20k which can measure wire distance and test it, connect the wire and see its length. Throw a new cable along the plinth or under the ceiling if it is a false panel.

Answer 2

If the cable in the wall consists of 4 pairs and 1 pair is out of order, then by lowering the speed to 100Mb / s you can live on the remaining pairs. The main thing is to find out which particular wires do not work and exclude them from work, and separate the rest instead of those that do not work.
I would dismantle the outlet in the office, short-circuit all the pairs in pairs, at the other end of the cable with an ordinary tester we find out which pairs work and which do not. We find 4 working wires and wire them for Ethernet 100BASE , we do not wire wires that are not used according to the standard (the color coding of wires, of course, will not be the same as in 568A / B, but the passage of an electrical signal does not depend on the color of the wire).

Answer 3

You don't measure anything in the wall. You go to the manager and voice 2 options:
1. Cable boxes around (cheap but dumb)
2. Directly a new line through the wall (expensive but beautiful)
Do as they say. Profit