How to test/debug bad network wiring?
I recently bought a place already wired with Cat 5E (8 ports, leading to a central closet). However attempting to get link, nothing works. On closer examination, it was obvious that the ends in the closet were wired backwards (brown on pin 1, etc). The jacks that I've pulled out of the wall do look to be correctly done. However, testing with a network cable tester shows zero link between any of the jacks and any of the ports in the closet - I had expected to just see a 1/8, 2/7, ... 8/1 mismatch, but instead get nothing at all.
The runs are accessible and look neat, though they take some bends that seem quite sharp and are in some cases much longer than they need to be (the person who put this in was a professional electrician but I suspect this was the first time he ran network cabling).
My best guess at this point is that he either bought bad cable, or put so much tension on it that he snapped wires. Though it seems surprising/unlikely that I wouldn't get at least one active wire on one of the 8 lines.
So, my question: is there anything else I should try or test before I go ripping out everything and running new cable?
Update: for the exciting conclusion, see my answer in this question below.
Don't run CAT6 cable
If the bends in your cable don't exceed the minimum bend radius for the cable type then it's not an issue.
If the cable lengths don't exceed the maximum cable length (in your case 100 meters/328 feet) then it's not an issue.
Why run new wiring when you can simply test the existing cable (not the terminations but the cable itself) and then reterminate one or both ends.
EDIT:
Considering there is so much contention on this, I've updated the answer:
There are two basic options here:
- Rewire. As mentioned above, if you can't be certain all the existing cabling is worth reusing, you may be better off starting from scratch. Hiring a contractor that will run everything, and certify the runs is certainly easier, but maybe not cheaper.
- Fix the problems with the existing cabling. Here you must check each cable run for shorts, and each end for proper termination, ensure the cables are run within specification, and within the specified bend radius. You should also determine if Plenium cabling has been run (if required). You should get a good cable tester/certifier, and check all the work after it has been corrected.
There is a cost/benefit tradeoff on either option. If you choose to go with the rewire, I personally see no reason to run older standards, unless the cost is truly too great to run CAT6a.
Last night I decided to reterminate the obviously bad ends in the wiring closet just to see what would happen (and because I haven't done my own cables in a few years and figured even if it did nothing I could use the practice). After reterminating I can get link on all ports. So seemingly they somehow managed to do everything OK except royally screwing up the network closet. I don't understand why my cable tester showed zero signal before, perhaps they had not crimped them tightly enough to get a good contact, used bad RJ45 connectors, or maybe my $6 cable tester was priced at that for a reason.
I'm accepting joeqwerty's answer because his advice re reterminating and testing before rewiring was sound. I'm still pretty skeptical of the cabling work, given the total newb errors in the terminating, and if I have troubles in the future I will likely rewire with 6a for 10 gigE so definitely a +1 for Cheekaleaks's answer as well. I don't really need 10 gigE, but the extra cost of 6a vs 5e pales in comparison to my labor input in rewiring, so a new 5e install wouldn't make sense here.
Thank you both for your responses.