PoE, Comcast Modems, and Service Outages

Tue Mar 29 21:30:45 UTC 2022

On 3/29/22 2:24 PM, Aaron C. de Bruyn wrote:
> On Tue, Mar 29, 2022 at 12:20 PM Brie <bruns at 2mbit.com 
> <mailto:bruns at 2mbit.com>> wrote:
> 
>     Unifi/EdgeSwitch?
> 
> 
> Yeah.  Unfortunately.  USW-24-250.

Oh, I have quite a few of them in service.  They work great in my 
experience as long as you don't shove them in hot closets or cabinets 
and cause them to overheat.  Also, firmware has gotten a bit better over 
the years.

I have a lot of background in Ubnt stuff, so I'm a bit biased here.

> 
>     Yeah, you know when 24v passive POE is turned on because it kills the
>     port on the other end that aren't designed to handle it.  Your router
>     would likely have a dead eth port on it.
> 
> 
> I've never tested it with one of my routers, but a tech did accidentally 
> test it on a UniFi AP.  I'm still not sure how he ignored the warning 
> about sending 24 volts down the line, but the WAP didn't like it and 
> decided to refuse to work with anyone ever again. ;)

Yup, that's normal if its a more recent AP that wasn't designed for 24V 
passive (pretty much anything recent AP wise).

I've seen techs destroy ethernet ports on brand new laptops doing that. 
  Very expensive lesson :)

-- 
Brielle Bruns
The Summit Open Source Development Group
http://www.sosdg.org    /     http://www.ahbl.org