Ghosts in our 6 New Ubiquity Pros - provision issues.

Fri Jun 19 14:06:31 UTC 2015

That's possible but I if they are re-provisioning on a regular schedule I kind of doubt it.  It would be easy to test though.  Plug an AP directly into your switch with a quality pre-manufactured patch cord and see how it acts. If it exhibits the same symptom it is probably not cabling.   Also, have you checked your interface counters for any packet errors?  Don't forget to look at your controller because if the controller became unreachable for any length of time that could easily cause your APs to re-provision as they reconnect with the controller.  I might set up a ping every second from the site of the access points to the controller and make sure the availability of the controller is 100%.  If you are on Cisco switches you should have log messages regarding PoE be granted on particular ports as well as up down messages on the interfaces.  Do you see the ports going up and down?  It is important to have NTP on the APs and switches so that you can correlate events in time (i.e. did the AP reboot causing the Ethernet link to drop or did the link drop causing the reboot?)

Steven Naslund
Chicago IL

>Bob,  I've deployed tons of Ubiquiti gear, and have seen this problem before. It always turns out to be poor quality cable installation. POE does not tolerate low quality connectors, especially in outdoor environments. There are >many aspects to a quality cabling job, so the best thing you can do is seek out a qualified installer with outdoor POE experience. 
>
>The most common problem I see is people using crimp-on RJ45 connectors directly on the ends of their cable runs. This is not how structured cabling is designed to work, in particular because most crimp-on connectors are intended for >stranded copper wire (such as that used in very flexible patch cords, designed to run horizontally over only a few dozens of feet), whereas the "riser" and "plenum" cable used for long-distance runs has solid core wires. The tiny >teeth in standard crimp connectors are designed to penetrate stranded wire, to make a solid electrical contact. With solid core wire, they just bend to the side of the copper core, making tenuous contact, which will conduct POE >current poorly (resulting in the resets you see) and eventually fail altogether as the improper connection corrodes over time. 
>
>The correct installation process is to use "punch-down" RJ45 jacks at each end of the cable run, and connect from those jacks to your equipment (radio at one end, POE switch at the other). On the outdoor side, the jack/plug junction >needs to be in a NEMA weatherproof enclosure, with weathertight fittings. And, for human and equipment safety, you must use shielded Cat5e/6 cable anytime you go outdoors, grounding only one end (usually the radio end), and >protecting the cable with an inline lightning protector between the RJ45 jack  and the radio. 

>If you haven't done that, then that's the first thing to fix. 

>BTW, avoid homemade patch cables whenever possible. Quality factory cables are hydraulically pressed and the plug is hermetically fused for a vastly superior connection compared to anything you can do with simple hand crimpers. And >all outdoor cables must be UV-grade cabling with weatherproof sheathing and water repellant inside (so-called "flooded" cable).

> -mel beckman