Ubiquiti AP to switch connection stuck at 100Mb

[teleos]

AP is an UAP AC IW Pro, and it is supposed to support GbE. Switch is an US 48 750W, and most of the ports are running GbE. The connection from this AP to the switch is showing 100Mb and I can't figure out why.

On the AP side, I couldn't find link speed configuration, tried power cycle with no effect.

On the switch side, the port configuration was automatic and I manually set it to 1Gbps to no avail either. Power cycle didn't help.

Can someone help me?

 

[Brandon Kahler]

That sounds like cabling or a termination issue.

 

[Kyuu]

Agreed, check the cabling/terminations. Did you make a new run for this AP or has some other device used this same connection at gigabit speed previously? Was it pre-terminated or did you do the terminations yourself?

 

[Andrewcw]

Are you using the Ubiquiti branded POE injector with your Switch for some weird reason? I've had a lot of these make the AP negotiate at 10/100.

 

[Paladin]

Don't manually set the speed, that will nearly always fail to improve anything and can make things much worse. A link that automatically goes to 100 megabit but works properly is better than one end at 100 and the other at 1000, or one end at 1000 and the other end not linked at all.

The likely culprit is either poor termination of the cable, poor quality cable or damage, or the run is too long or is suffering heavy noise at some point that is causing very bad signal integrity at 1000 megabit.

 

[teleos]

Thank you all for your quick response!

The whole network was set up a few years ago and I believe it has been running at 100Mb for a while, it's just nobody noticed problem before. The cabling was probably done even earlier.

I don't believe there is a PoE injector, the AP is running on PoE directly.

Let me see how I can check the cable.

 

[teleos]

Weirdest thing happened, the port changed to Gb before I did anything.

I have another AP that has the same problem, let me see if I can stare that one down as well.

 

[Kyuu]

I would still inspect the terminations, as the fact that it's changing speed like that indicates it's on the margins of working at gigabit speed and will likely negotiate back down to 100mbit intermittently. You also may get random packet loss when it's operating at gigabit.

In my experience, the likely culprits are, in order of likelihood:

1) Substandard terminations. 90%+ of issues are due to this.
2) Damaged cable, due to damage incurred while being pulled/installed, people damaging it later while working on the vicinity, animal activity, etc.
3) Run is too long, over 100 meters
4) Unshielded cable in a noisy RF environment and/or run adjacent to high-voltage power

 

[teleos]

I would still inspect the terminations, as the fact that it's changing speed like that indicates it's on the margins of working at gigabit speed and will likely negotiate back down to 100mbit intermittently. You also may get random packet loss when it's operating at gigabit.

How should I check?

 

[brendan_kearney]

what i have... simple but effective.

https://www.lowes.com/pd/Sperry-Cab...oax-and-Cat3-through-Cat6-Ethernet/5001794639

 

[Kyuu]

As the previous poster linked to, you can use a relatively cheap cable tester to try to find faults. You can also just visually check what is accessible. I very much hope that all terminations are in accessible places (behind wall plates, at the end of the cable runs) and you don't have random splices in crawl-spaces.

 

[teleos]

Thanks again! I think I know what I need to do now. The AP is installed on top of a wall plate, I just need to figure out how to take it off.

 

[teleos]

From watching installations videos, the face plate of the UAP-AC-IW can just be pulled off with some force? I was afraid of breaking it.

 

[Lord Evermore]

How should I check?

A cheap cable tester can tell you whether there's signal yes or no, and whether there's anything crossed, but it can't tell you anything beyond that such as whether the strength is marginal or there's interference, and it won't catch intermittent issues unless you just sit there staring at it for a while and maybe jiggling the ends of the cables. I usually just go with re-terminating the ends one by one and seeing whether it's fixed after each. A cable tester is still handy to have around and is good to use anytime you make or re-make cables.

 

[Lord Evermore]

From watching installations videos, the face plate of the UAP-AC-IW can just be pulled off with some force? I was afraid of breaking it.

Check the bottom. There may be a security screw. Other than that there seems to be a tab at the top you'll need to use a screwdriver to release. It can probably come off just by pulling, but you're risking snapping that tab off and then it may not stay in place.
https://dl.ubnt.com/qsg/UAP-AC-IW-PRO/UAP-AC-IW-PRO_EN.html

 

[teleos]

Check the bottom. There may be a security screw. Other than that there seems to be a tab at the top you'll need to use a screwdriver to release. It can probably come off just by pulling, but you're risking snapping that tab off and then it may not stay in place.
https://dl.ubnt.com/qsg/UAP-AC-IW-PRO/UAP-AC-IW-PRO_EN.html

Much appreciated! There seems to be much less information for the Pro model vs. the regular model.

I'll use a screwdriver.

 

[Kyuu]

What our good Lord Evermore said is true... sometimes a termination will look fine visually and will test okay yet still cause problems. Sometimes you can catch that one of the pins is making bad contact by wiggling the cable around with it plugged into the cable tester. If you have a problematic connection and can't identify the problem, reterminating anyway is sometimes the answer. If you have the tools/parts and are confident in your skill, anyway.

 

[Lord Evermore]

Oh, and if the cable doesn't have the sheath stuck into the connector, just re-terminate it, period. Cables are not meant to be depending on the individual wires for the strength of the attachment, even when you think it's not really going to be moving after it's plugged in. And make sure both the connector and the cable are the same CAT rating, because that affects the thickness of the wires and the sheathing, which can affect the strength of the crimp.

If there's a punch-down panel on the other end, or the end by the AP is a punch-down jack, obviously no sheathing should be in there but also as little removed as possible, and should be re-terminated anyway if you're having problems. When my last employer's office was built out, our contractor for all the wiring ran like 24 wall jacks (and a few years later added some more) and we only discovered after a few years that several of them were no good, only connected at 100Mb, and I had to re-terminate, in some cases at the jack and others at the panel. They used cable testers on all of them during the work, and I tested them as well, and they looked like they were okay. Contractors are rushing and paid by the jack, not the amount of time they spend on it.

 

[heartburnkid]

Are you using the Ubiquiti branded POE injector with your Switch for some weird reason? I've had a lot of these make the AP negotiate at 10/100.

IME, the older (black) injectors restrict the connection to 10/100, but the newer (white) ones do not.

 

[heartburnkid]

Weirdest thing happened, the port changed to Gb before I did anything.

I have another AP that has the same problem, let me see if I can stare that one down as well.

This is 100% a cabling issue. Likely one of the ends was jostled slightly and managed to make connection again, or possibly there might be a break somewhere else in the cable.

I'd re-terminate both ends just to make sure it doesn't fail back to 100Mbps again.

 

[teleos]

Oh, and if the cable doesn't have the sheath stuck into the connector, just re-terminate it, period. Cables are not meant to be depending on the individual wires for the strength of the attachment, even when you think it's not really going to be moving after it's plugged in. And make sure both the connector and the cable are the same CAT rating, because that affects the thickness of the wires and the sheathing, which can affect the strength of the crimp.

If there's a punch-down panel on the other end, or the end by the AP is a punch-down jack, obviously no sheathing should be in there but also as little removed as possible, and should be re-terminated anyway if you're having problems. When my last employer's office was built out, our contractor for all the wiring ran like 24 wall jacks (and a few years later added some more) and we only discovered after a few years that several of them were no good, only connected at 100Mb, and I had to re-terminate, in some cases at the jack and others at the panel. They used cable testers on all of them during the work, and I tested them as well, and they looked like they were okay. Contractors are rushing and paid by the jack, not the amount of time they spend on it.

Thanks again for all the details! I'm pretending to be our network admin at this point, I'm really more of a software & chip person myself.

I'll most likely come back with more questions after I look at it in more detail.

 

[Lord Evermore]

IME, the older (black) injectors restrict the connection to 10/100, but the newer (white) ones do not.

They haven't produced those for years, but yes, those earliest 24V passive injectors were 10/100-only (which was fine for the APs at the time, in terms of real throughput requirements). However this AP wasn't produced during that period, and is only capable of using 48V PoE.

 

[teleos]

I did manage to look at the AP side but the termination looks pretty good to my untrained eyes.

The switch side I believe goes through a patch panel, I'll try to take a look tomorrow.

 

[Lord Evermore]

I did manage to look at the AP side but the termination looks pretty good to my untrained eyes.

The switch side I believe goes through a patch panel, I'll try to take a look tomorrow.

Don't depend on your eye, trained or not. They almost always LOOK good. By all means check both sides for anything obvious, but don't just skip re-termination entirely based on appearance. You'll hate yourself if you keep troubleshooting for hours then go back and finally do it and the problem is fixed with five minutes of effort. (Or a little more if you're not experienced doing terminations. Or you're colorblind. Or fumble-fingered. I've had more than one instance where I re-terminated then had to do it again after finding a pin didn't connect.)

 

[heartburnkid]

They haven't produced those for years, but yes, those earliest 24V passive injectors were 10/100-only (which was fine for the APs at the time, in terms of real throughput requirements). However this AP wasn't produced during that period, and is only capable of using 48V PoE.

They actually do still make passive adapters, though they use the white shells for those too now (and they can support GbE without issue). They're mostly made for UISP gear (Nanostation/Gigabeam/etc), but the Unifi APs will support them as well as the standard ones.

You can tell them apart by the label under the Ubiquiti logo. Standard ones will be labeled with the standard they support (af/at), while passive ones will be labeled by their voltage (24V/48V).

 

[Lord Evermore]

They actually do still make passive adapters, though they use the white shells for those too now

That's why I said "those" in reference to the oldest black injectors, which specifically only supported 10/100. (They did also make black ones that did 1Gb.) There are still other brands of 10/100 injectors, even af/at models. Can't really see why anybody bothers to make that; can't be that much of a cost difference and it means having to maintain another production line. Ubiquiti's site store doesn't even list any passive injectors as a separate product to buy.

 

[Kyuu]

Ubiquiti's site store doesn't even list any passive injectors as a separate product to buy.

Hmm, I don't think you checked the UISP store.

 

[Lord Evermore]

Hmm, I don't think you checked the UISP store.

Well I went to the store and went to the page that most people will find by default, not realizing they had a separate set of listings now for UISP and whatever AmpliFi is. The last time I looked at Ubiquiti's site they didn't have things broken out like that but it was over two years ago. I think I can be forgiven for thinking that if it's not listed in their "power accessories" products then they don't sell it, and clearly they don't intend to sell it for people buying consumer UniFi products anymore. (Kind of odd since a business of any kind is a lot more likely to have a PoE switch with standard active PoE and to be buying multiple APs that support at/af, while a consumer is a lot more likely to just need a cheap passive injector for a single AP.)

 

[KD5MDK]

There are probably 3 cables involved:
Switch <patch cable> patch panel <in wall cable> wall plate <patch cable> AP
It might be worth reseating each of the patch cables at each end before doing anything more complicated if you haven't done that already.

If you can disconnect the AP from the wall, I'd carry it over to the switch and plug it into a different port with a new patch cable.
If that works, you've isolated the issue to the cabling. Also gives you a good chance to isolate out the switch port as well. Unplug the patch cable running from switch to the patch panel and plug the AP into that cable. If it still works, you know the problem is between the patch panel and the far end.

 

[Kyuu]

Well I went to the store and went to the page that most people will find by default, not realizing they had a separate set of listings now for UISP and whatever AmpliFi is. The last time I looked at Ubiquiti's site they didn't have things broken out like that but it was over two years ago. I think I can be forgiven for thinking that if it's not listed in their "power accessories" products then they don't sell it, and clearly they don't intend to sell it for people buying consumer UniFi products anymore. (Kind of odd since a business of any kind is a lot more likely to have a PoE switch with standard active PoE and to be buying multiple APs that support at/af, while a consumer is a lot more likely to just need a cheap passive injector for a single AP.)

Fair, that probably came across more snarky than I intended. Sorry.

 

[Lord Evermore]

Fair, that probably came across more snarky than I intended. Sorry.

It wasn't that bad. Probably in line with the way I often say things.

 

[teleos]

There are probably 3 cables involved:
Switch <patch cable> patch panel <in wall cable> wall plate <patch cable> AP
It might be worth reseating each of the patch cables at each end before doing anything more complicated if you haven't done that already.

I think there are only two cables, as the in-wall cable directly connects to the AP. Unfortunately it is working at Gb now, I'll see what I can do about termination.

 

[KD5MDK]

Ok, so the in wall cable terminates in an RJ-45 plug? Fair enough, removes one failure point and adds another tool required for retermination.

 

[teleos]

Ok, so the in wall cable terminates in an RJ-45 plug? Fair enough, removes one failure point and adds another tool required for retermination.

Yes, it directly terminates in an RJ-45 plug. It seems everyone is telling me to re-terminate

 

[Lord Evermore]

I bet if you jiggle the cable while you're performing a file transfer you'll see the transfer halt then restart, halt then restart, maybe slower sometimes, maybe at full speed.

There is always the slight chance that the port on the AP is going bad, or the switch port, but that's a VERY small chance. If the end by the switch is using a patch panel or wall jack, then the patch cable to the switch could also be at fault.

But it's probably the case that it's been like this ever since the AP was installed (or whatever else was using that connection before) and nobody noticed. I don't know how you even caught it, but I'd guess it's not getting such high usage that it even mattered, possibly until now.

One thing I just thought of, nobody else seems to have asked, it is Cat5e or Cat6 cabling, right? (And matching connector.)

 

[stevenkan]

Check the bottom. There may be a security screw. Other than that there seems to be a tab at the top you'll need to use a screwdriver to release. It can probably come off just by pulling, but you're risking snapping that tab off and then it may not stay in place.
https://dl.ubnt.com/qsg/UAP-AC-IW-PRO/UAP-AC-IW-PRO_EN.html

Whenever I buy a Ubiquiti AP the first thing I do is break off that frickin' tab. No one wants find the tiny, invisible hole with a sharp object when they're on a ladder, and the friction on the thing is enough to hold it in place anyway. Stupid design </rant>

 

[stevenkan]

How should I check?

I quite like my PockEthernet unit. It produces reports like:

or

or

 

[Lord Evermore]

Whenever I buy a Ubiquiti AP the first thing I do is break off that frickin' tab. No one wants find the tiny, invisible hole with a sharp object when they're on a ladder, and the friction on the thing is enough to hold it in place anyway. Stupid design </rant>

I don't know what type of latch/clip the round models use now but the flat clip on them was absolutely horrid. It's really hard to visually tell where on the circle it's located without getting up on the ladder and moving your eyes or fingers all the way around the edge to find the tiny hole (with your face pushed against the wall/ceiling), or the cable notch that may or may not have a plug in it, unless you leave the cable exposed and remember the position relative to the latch. You have to use a very thin device because you've only got a couple of mm of space and it can't be a big screwdriver since the angle with the ceiling or wall is too close, and you can't tell if you've lifted it far enough so you have to be pushing with one hand while trying to twist it at the same time, and trying to remember which direction to turn it because you hardly ever have to take them down. Then they made the ones with a clip that you push inward, but it's really hard to push, and you still can't really tell if it's pushed far enough, and the plastic is soft so it deforms and can end up in a shape that CAN'T be properly released. I usually ended up being those until they just never would catch. The plastic was so soft it was too much work to try to break it off.

 

[stevenkan]

I don't know what type of latch/clip the round models use now but the flat clip on them was absolutely horrid. It's really hard to visually tell where on the circle it's located without getting up on the ladder and moving your eyes or fingers all the way around the edge to find the tiny hole (with your face pushed against the wall/ceiling), or the cable notch that may or may not have a plug in it, unless you leave the cable exposed and remember the position relative to the latch. You have to use a very thin device because you've only got a couple of mm of space and it can't be a big screwdriver since the angle with the ceiling or wall is too close, and you can't tell if you've lifted it far enough so you have to be pushing with one hand while trying to twist it at the same time, and trying to remember which direction to turn it because you hardly ever have to take them down. Then they made the ones with a clip that you push inward, but it's really hard to push, and you still can't really tell if it's pushed far enough, and the plastic is soft so it deforms and can end up in a shape that CAN'T be properly released. I usually ended up being those until they just never would catch. The plastic was so soft it was too much work to try to break it off.

It sounds like you them slightly better than I do.

 

[Lord Evermore]

It sounds like you them slightly better than I do.

Not sure if you mean the clips or the APs. As far as the APs, they were relatively inexpensive, had a good reputation, had a good control panel for multiple devices so they were good for small businesses (and later went to cloud controller for multiple locations), and were good enough in performance, though optimized more for high numbers of users than individual throughput. It was what my company (MSP) went with after our Director of IT researched things, and were better than the other lower-cost stuff, and there wasn't a pressing need to spend more time trying to find better ones. We did start using WatchGuard more a few years before I left, but Ubiquiti was still the go-to for small clients since WatchGuard were pretty expensive and required subscriptions.

But on the clips, I just tried to not have to take them down very often, bitched when I did, and moved on.