01-17-2018 11:19 AM - edited 07-05-2021 08:07 AM
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.
01-17-2018 11:13 PM
12W on a Meraki switch. No issues with connectivity.
01-24-2018 12:29 PM
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.
01-24-2018 05:55 PM
@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".
01-24-2018 06:44 PM
05-16-2018 05:07 AM
Disable CDP on Juniper if it's enabled.
It's possible that Juniper is bringing a wrong PoE budget information via CDP.
05-16-2018 05:24 AM
10-25-2018 04:40 PM
Just checking. Was this ever resolved?
10-29-2018 11:39 AM
No we never determined root cause. We replaced the APs.
04-16-2021 03:31 AM
Hello,
our 3802i show the same behaviour in power consumption on our Cisco SG350-10P switches:
On Port gi1 is a 3802i using only 10,8 Watt and on Ports gi2-gi4 3 old Cisco 1142-APs are connected.
Unit Module Nominal Consumed Temp SW PSE chipset
Power (W) Power (W) (C) Version HW Revision
---- -------------- --------- ------------ -------- ------------- -----------------
1 SG350-10P 62 57 (92%) 73 23.190.18.3 PD69208 - 0x4A02
Interface Admin Oper Power (W) Class Device Priority
---------- ---------- ----------- ----------------- ----- -------------- --------
gi1 Auto On 10.800 4 low
gi2 Auto On 9.600 (15.400) 3 low
gi3 Auto On 11.500 (15.400) 3 low
gi4 Auto On 10.300 (15.400) 3 low
The show cdp nei detail reveals also the Full/Half-Duplex-Mismatch Bug with the new Csico 2800/3800-series-APs:
Device-ID: D20-HVT
Advertisement version: 2
Platform: cisco AIR-AP3802I-E-K9
Capabilities: Router TransBridge
Interface: gi1, Port ID (outgoing port): GigabitEthernet0
Holdtime: 114
Version: Cisco AP Software, ap3g3-k9w8 Version: 8.3.141.0
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 2014-2015 by Cisco Systems, Inc.
Duplex: half
Primary Management Address: IP 10.232.4.193
Addresses:
IP 10.232.4.193
---------------------------------------------
But cdp does not show any info about the Power drawn.
The WLAN AP and the antennas are working.
We are not sure about any restriction on WLAN AP functionality.
I fear that maybe special functions like beamforming will not working with only 10 Watt.
But I'm not sure.
Does anyone know if this is a nice power-saving-feature or a bug with the Cisco 3802-APs?
Thank You
Wini
04-16-2021 03:33 AM
Hello,
our 3802i show the same behaviour in power consumption on our Cisco SG350-10P switches:
On Port gi1 is a 3802i using only 10,8 Watt and on Ports gi2-gi4 3 old Cisco 1142-APs are connected.
One can see that the nominal value in brackets () is missing for the 3802-AP in comparision to the old 1142-APs:
Unit Module Nominal Consumed Temp SW PSE chipset
Power (W) Power (W) (C) Version HW Revision
---- -------------- --------- ------------ -------- ------------- -----------------
1 SG350-10P 62 57 (92%) 73 23.190.18.3 PD69208 - 0x4A02
Interface Admin Oper Power (W) Class Device Priority
---------- ---------- ----------- ----------------- ----- -------------- --------
gi1 Auto On 10.800 4 low
gi2 Auto On 9.600 (15.400) 3 low
gi3 Auto On 11.500 (15.400) 3 low
gi4 Auto On 10.300 (15.400) 3 low
The show cdp nei detail reveals also the Full/Half-Duplex-Mismatch Bug with the new Csico 2800/3800-series-APs:
Device-ID: D20-HVT
Advertisement version: 2
Platform: cisco AIR-AP3802I-E-K9
Capabilities: Router TransBridge
Interface: gi1, Port ID (outgoing port): GigabitEthernet0
Holdtime: 114
Version: Cisco AP Software, ap3g3-k9w8 Version: 8.3.141.0
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 2014-2015 by Cisco Systems, Inc.
Duplex: half
Primary Management Address: IP 10.232.4.193
Addresses:
IP 10.232.4.193
---------------------------------------------
But cdp does not show any info about the Power drawn.
The WLAN AP and the antennas are working.
We are not sure about any restriction on WLAN AP functionality.
I fear that maybe special functions like beamforming will not working with only 10 Watt.
But I'm not sure.
Does anyone know if this is a nice power-saving-feature or a bug with the Cisco 3802-APs?
Thank You
Wini
04-19-2021 06:50 AM
Have a read here: https://www.cisco.com/c/en/us/support/docs/field-notices/702/fn70252.html It seems you should upgrade to 8.3.150.0 or newer.
Regarding the power, you have a 60 W budget, of which ports 2-4 already use a lot. You actually already use 92% of available power, not enough for the 3800 left.
06-04-2024 04:14 AM
Check if the Juniper switch has LLDP-Med enabled so to negotiate PoE budget with the devices:
https://www.juniper.net/documentation/us/en/software/junos/cli-reference/topics/ref/statement/lldp-med-lldp.html
Discover and save your favorite ideas. Come back to expert answers, step-by-step guides, recent topics, and more.
New here? Get started with these tips. How to use Community New member guide