Ubiquiti error...

RedvGreen · 21 May 2019 at 21:11

Until today I’ve been running a successful wireless network comprising:

1 x 8Port POE switch 60W (5-8 are POE)

With the following connected via cat6 POE:
1 x Cloudkey
2 x APAC LR

Now, today, I ran a Cat6 run from the Switch in the loft, outside the house, over the Sky Dish cable directly behind the dish, into the lower room downstairs, approx 15m.

Cable tested (basic) all passed.

Attached new AP AC LR and it it going mental.

It alternates between...
Connected (wireless uplink)
to
Isolated

I’ve swapped the cables at the switch and the existing APs work fine on port 8.

I’ve recrimped with new RJ45 and the same problem exists.

Ive yet to swap the APs around to test the cables, but there is clearly a problem. The switch indicates POE is active but no data is transferring - it will only adopt and connect wirelessly to a weak signal from the closest other AP.

Any ideas what the problem may be here? I don’t think the Sky cable will cause interference as both the cat6 and the Sky Cable will be shielded. I’m wondering if the sky dish itself is causing interference?

Also considering that the AP may be faulty too.

bremen1874 · 21 May 2019 at 21:17

Basic cable testers can show okay even when the wiring is wrong.

Can you post pictures of your crimped on plugs showing the wire colours?

RedvGreen · 21 May 2019 at 21:33

Switch crimp:

AP crimp:

They are both wired:

Orange/white
Orange
Green/white
Blue
Blue/white
Green
Brown/white
Brown

bremen1874 · 21 May 2019 at 21:40

They do look okay. It'd have been nice to get the jacket under the cable clamp, but that's not going to stop them working.

That isn't shielded cable, but it doesn't need to be. I would have used external grade cable if it's going outside.

Try connecting something else (laptop?) using the same cable run and see if that works.

RedvGreen · 21 May 2019 at 21:43

bremen1874 said:
They do look okay. It'd have been nice to get the jacket under the cable clamp, but that's not going to stop them working.

That isn't shielded cable, but it doesn't need to be. I would have used external grade cable if it's going outside.

Try connecting something else (laptop?) using the same cable run and see if that works.

It did have a blue/silver foil around the full sets of twisted pairs and the annoying central ‘+’ core too. I always thought this was outdoor proof?!

I’ll patch the loft cable into the non-POE switch port and try a laptop as you say...

bremen1874 · 21 May 2019 at 21:49

Why use shielded cable with unshielded plugs? The shielding is supposed to connect the metal body of the plug and from there to the socket it's plugged into.

That appears to be PVC cable. If it is it'll degrade in sunlight (but it will take a while depending on where it's situated).

I'd have used external grade Cat5e UTP for that job.

RedvGreen · 21 May 2019 at 21:53

bremen1874 said:
Why use shielded cable with unshielded plugs? The shielding is supposed to connect the metal body of the plug and from there to the socket it's plugged into.

That appears to be PVC cable. If it is it'll degrade in sunlight (but it will take a while depending on where it's situated).

I'd have used external grade Cat5e UTP for that job.

Live and learn about the rj45s, this was all I could buy at Screwfix today !

I have two runs of this cable around 7m exposed to elements, looks like I may have to re-lay the cabling then...

bremen1874 · 21 May 2019 at 21:57

PVC cable can last for years, especially if it's in a shady area.

If you can get what you have working I'd leave it alone for now.

RedvGreen · 21 May 2019 at 22:05

bremen1874 said:
PVC cable can last for years, especially if it's in a shady area.

If you can get what you have working I'd leave it alone for now.

Well unfortunately the exposed element of the cabling gets full sun all day...!

bremen1874 · 21 May 2019 at 22:13

Check what the cable jacket is actually made from. It looks like PVC but it might not be.

RedvGreen · 21 May 2019 at 22:49

bremen1874 said:
Check what the cable jacket is actually made from. It looks like PVC but it might not be.

Interestingly, the fresh cable was only performing at 10Mbps, whilst another was returning 1Gbps...

bremen1874 · 21 May 2019 at 22:55

10Mbps?

It's not unusual to find that cable runs at 100Mbps instead of Gigabit because of a bad crimp (100Mbps only requires two of the pairs, Gigabit needs all four).

RedvGreen · 21 May 2019 at 23:00

bremen1874 said:
10Mbps?

It's not unusual to find that cable runs at 100Mbps instead of Gigabit because of a bad crimp (100Mbps only requires two of the pairs, Gigabit needs all four).

Yup! I’m thinking the cable may be faulty or damaged somewhere along the 15m run.

Any recommendations for national stores that sell decent external shielded Cat6?

bremen1874 · 21 May 2019 at 23:10

You don't need Cat6 or shielded cable.

Keep life simple and use external grade Cat5e UTP.

I tend to buy cable from Comms Express but they aren't going to have lengths below 100m.

For shorter lengths eBay is worth a look, just make sure it's 100% copper they're selling.

bledd · 22 May 2019 at 07:31

Your cable tester, which type do you have? Did you check both ends of the tester?

Often the sender unit will ask light up. It's the receiver you want to look at.

Poorly crimped ends. Show a closer picture of them, cables may not be all the way in.

You want the jacket in the plug.

RedvGreen · 22 May 2019 at 08:12

bledd said:
Your cable tester, which type do you have? Did you check both ends of the tester?

Often the sender unit will ask light up. It's the receiver you want to look at.

Poorly crimped ends. Show a closer picture of them, cables may not be all the way in.

You want the jacket in the plug.

The tester is a straight-forward short and mis-wire check. This is the exact one:

I don’t think it’s possible to produce photos any closer than what’s been provided! For reference, I’ve crimped every other cable in the house (around 40) and they’ve been fine for 1.5yrs.

the-evaluator · 22 May 2019 at 09:02

As daft as it sounds, try a different firmware on the new AP.

I had the exact same problem with an AC-Lite and after scratching my head for days and trying different switch ports, switches, cables and even using a known good PoE injector I downgraded the firmware. It connected fine, I then upgraded the firmware (so it went back to the firmware it arrived with) and it's been fine ever since through various firmware upgrades.

If you bring the new AP closer to an existing AP then the wireless uplink should be stable enough to let you change the firmware.

RedvGreen · 22 May 2019 at 10:25

the-evaluator said:
As daft as it sounds, try a different firmware on the new AP.

I had the exact same problem with an AC-Lite and after scratching my head for days and trying different switch ports, switches, cables and even using a known good PoE injector I downgraded the firmware. It connected fine, I then upgraded the firmware (so it went back to the firmware it arrived with) and it's been fine ever since through various firmware upgrades.

If you bring the new AP closer to an existing AP then the wireless uplink should be stable enough to let you change the firmware.

I’ve just laid 40 floorboards so far today, I’m going to jump to this cable issue now.

I’m going to connect the AP directly to the switch using a 0.5m cable and see what happens there; it could well be an AP issue as you suggest but this will hopefully diagnose it a bit better.

I’ll then patch the new cable into the main switch and try the laptop on that, Incase the UniFi PoE switch is dialing back the speed for some reason.

RedvGreen · 22 May 2019 at 12:26

I purchased a different cable tester and it indicated a fault in core 2. I recrimped both ends and it passed the tester.

I’ve disabled the nearest AP to the new AP and reattached it (forcing Ethernet adoption) and it adopted perfectly. Unfortunately it has once again dropped to ‘connected (wireless)’ - connected to the Landing AP with 12% signal strength(!).

So far, I’ve ruled out:

- AP fault
- Switch fault
- Crimp fault

That leaves interference from sky dish and cable and cable damage (15m through two external cavity walls).

the-evaluator · 22 May 2019 at 12:39

The Sky dish shouldn't be a problem, I've got a run of cat 5e in the same trunking as the cable for my Sky dish and everything is working fine here.

Try and connect the new AP directly to the switch and see what happens. You could also disable wireless meshing completely and see if that helps, generally it's best to disable it if you don't need it as I find Ubiquiti stuff starts grumbling about STP when for some unknown reason it'll try and uplink wirelessly even though there's a working run of cat 5e in place.