Sorry for the vague title, but I can't really describe it more succinctly.
A friend of mine (who is also an electrician) put in some data ports throughout my house – one in the lounge, one in the theatre room, one in my office, and one in my shed. Here's a diagram:
I can plug a device into any outlet and get a connection, apart from the outlet in the shed (marked in red). However, if I bypass the central switch (only for the line that runs to the shed, highlighted below) then I do get a connection in the shed:
Here are a list of things we've tried to rectify this:
- Completely replacing the line running to the shed, just in case it was in some way at fault
- Ensuring the line to the shed is pulled away from nearby electrical cabling, just in case interference was to blame
- Enclosing the line to the shed in conduit to further minimize any potential electrical interference
- Replacing the lead between the central switch and the router
- Replacing the lead from the 4 gang wall outlet to the switch
- Detaching everything else from the switch and only attaching the line to the shed
- Swapping to a different port on the switch (just in case one port was faulty)
- Swapping the two switches around
None of these things has worked and we're completely baffled. Can anyone offer any explanation and resolution to this issue?
EDIT (after several comments):
Some extra info:
- The electrician did test the wiring using a testing tool, and it reports a positive result
- It's Cat6 cabling
- I used the same device (a laptop running Linux Mint 17) to test every port
- I just printed out my floor plan and measured distances from the switch to both the shed and lounge. The straight-line distance to shed is shorter, but the path is more circuitous, so I think the cabling length would be longer by around 4 to 5 metres, but we're still only talking 25-30 metres long
- The shortcut cable I used was different because I needed a longer one for the shortcut. However, I did try multiple cables in every position, so I don't think it's the cable. To be certain, I just used the shortcut cable between the switch and 4-gang outlet, and the connection in the shed still doesn't work
Best Answer
What's the cable length from the shed to the switch? Ethernet is limited to 100 m, but your switch has "Green technology". This reduces the power used to transmit (which is in violation of the standard) and makes transmission unreliable near the 100 m maximum. They assume the equipment will be used in SOHO environment where the cabling rarely exceeds 20 m.
Also keep in mind that the Cat 5(e) standard was made for 90 m of solid core wire and 10 m of stranded wire. You must use the right terminators as well, or connection will be unreliable.