topic Re: 3802 PoE Power draw. in Wireless

3802 PoE Power draw.

JASON SIMMONS — Mon, 05 Jul 2021 15:07:14 GMT

How much power are your 3802 access points drawing from your PoE switches? Are they Cisco switches? We have an installation of 3802s connected to a non-Cisco 802.3at enabled switch and we're seeing a maximum 11w to each AP. A consultant was expecting to see somewhere between 15-25w. It appears that all the radios are up but users have been complaining about peformance and connectivity since they were installed.

Re: 3802 PoE Power draw.

Leo Laohoo — Wed, 17 Jan 2018 19:43:28 GMT

3802 chews up 29w PoE.

Try enabling LLDP on the switch.

The new generation of APs behave differently now. I have seen 1560 (which the 2800/3800 share the same code with) negotiate LLDP first before negotiating to Cisco's proprietary CDP.

Can you also console or remote into the AP and post the complete output to the following commands:

1. sh cdp inline; and

2. sh lldp inline

I've hit a bug with the 1562 where they would draw the right amount of power and complain that they aren't.

Re: 3802 PoE Power draw.

JASON SIMMONS — Mon, 03 Jun 2024 13:55:06 GMT

LLDP is enabled on the switch

edited

Re: 3802 PoE Power draw.

Leo Laohoo — Wed, 17 Jan 2018 19:59:10 GMT

What firmware is the controller running on?
Exactly what kind of 3rd party injectors are these?

Another thing: I'd like to ask if you can console (has to be console) into one of the 3800 and reboot. I want to see the entire boot-up process. Pay particular attention near the end because this is where the AP will attempt to negotiate power.

Re: 3802 PoE Power draw.

JASON SIMMONS — Wed, 17 Jan 2018 19:58:29 GMT

no injectors. Juniper ex-4300-48P switch

Re: 3802 PoE Power draw.

JASON SIMMONS — Mon, 03 Jun 2024 13:52:30 GMT

deleted

Re: 3802 PoE Power draw.

JASON SIMMONS — Wed, 17 Jan 2018 22:40:50 GMT

controller's running 8.2.166.0

Sorry. Got a lot going on today.

Re: 3802 PoE Power draw.

Leo Laohoo — Thu, 18 Jan 2018 02:28:47 GMT

CSCvd86274

Re: 3802 PoE Power draw.

JASON SIMMONS — Thu, 18 Jan 2018 02:38:18 GMT

I don't understand how that big is related to my issue.

Re: 3802 PoE Power draw.

Leo Laohoo — Thu, 18 Jan 2018 02:40:01 GMT

Ap is not sending out CDP. NO CDP, no PoE negotiation.

Re: 3802 PoE Power draw.

JASON SIMMONS — Thu, 18 Jan 2018 02:47:39 GMT

But it isn't a Cisco switch. The same goes for LLDP? I'm not running those versions of code.

Re: 3802 PoE Power draw.

Leo Laohoo — Thu, 18 Jan 2018 02:58:57 GMT

Good point. Both of them.
When it comes to information found in Bug IDs, don't trust them fully. Most of the time, the Known Affected Versions &/or Known Fixed Versions are rarely updated.
I would, however, recommend you raise a TAC Case and get TAC to investigate.

Re: 3802 PoE Power draw.

Leo Laohoo — Thu, 18 Jan 2018 04:34:32 GMT

Another thing, can you force the Juniper switch to push 30w PoE to the port (static power assignment)?

Re: 3802 PoE Power draw.

JASON SIMMONS — Mon, 03 Jun 2024 13:53:29 GMT

I have a TAC case open, SR XXXXXXXXXXXX.

I've searched Juniper's KBs and haven't been able to find a way to force a certian wattage. The max available per port is 30w BTW. I'm planning on opening a case with them in the morning.

I'll try resetting the AP using the process in the bug ID and will report back.

Re: 3802 PoE Power draw.

Scott Fella — Thu, 18 Jan 2018 07:13:39 GMT

12W on a Meraki switch. No issues with connectivity.

Re: 3802 PoE Power draw.

Saravanan Lakshmanan — Sun, 21 Jan 2018 05:27:08 GMT

https://www.juniper.net/documentation/en_US/junos/topics/task/configuration/poe-cli.html

user@switch# set poe interface ge-0/0/5 maximum-power <value>

Re: 3802 PoE Power draw.

JASON SIMMONS — Wed, 24 Jan 2018 20:29:56 GMT

I learned and configured the switch to statically assign 30W and I'm still getting 11.x watts, although I saw it jump to 13w once. Cisco TAC basically said it isn't compatible and told me to buy an injector...

I honestly don't know if power is the problem. I just know installing the older switches worked.

I don't know...

Thanks for your replies.

Re: 3802 PoE Power draw.

Leo Laohoo — Thu, 25 Jan 2018 01:55:50 GMT

@JASON SIMMONS wrote:

I learned and configured the switch to statically assign 30W and I'm still getting 11.x watts, although I saw it jump to 13w once. Cisco TAC basically said it isn't compatible and told me to buy an injector...

I honestly don't know if power is the problem. I just know installing the older switches worked.

No, it's a bug with the AP software. It seems that AP is having difficulty negotiating power if it's not Cisco.

I believe TAC would say that "it's not supported".

Re: 3802 PoE Power draw.

Scott Fella — Thu, 25 Jan 2018 02:44:07 GMT

Power should not be a problem… Mine changes to up to 13W and drops down also.

Re: 3802 PoE Power draw.

hogerappa — Wed, 16 May 2018 12:07:21 GMT

Disable CDP on Juniper if it's enabled.

It's possible that Juniper is bringing a wrong PoE budget information via CDP.