WAP571-A-K9 PoE+ issue on WS-C2960X-48FPS-L

[antonio1dente]

Hello,

I am installing my new WAP571-A-K9 and I am facing an issue with PoE+ negotiation. The AP is running on 802.3af even if the source is 802.3at capable.

Actions already taken:

• upgrade WAP571 to latest firmware available 1.0.1.9.
• on WAP571 set lldp PoE priority to "critical".
• on 2960X - set power inline to static 30W.
• disable lldp tlv power management on the port.
• global lldp has been activated.

still no luck.

The switch is a stack of 3 2960X PoE switches:

Switch Ports Model              SW Version     SW Image
------ ----- -----              ----------     ----------
* 1    28    WS-C2960X-24PS-L   15.2(2)E6      C2960X-UNIVERSALK9-M
2      52    WS-C2960X-48FPS-L  15.2(2)E6      C2960X-UNIVERSALK9-M
3      52    WS-C2960X-48FPS-L  15.2(2)E6      C2960X-UNIVERSALK9-M

this is the configuration on the port Gi2/0/11:

switchport trunk allowed vlan 1,5-7,98
switchport mode trunk
power inline static
no lldp tlv-select power-management
no lldp med-tlv-select power-management
spanning-tree portfast trunk

SWITCH#sh power inline

Module Available Used     Remaining
        (Watts) (Watts)    (Watts)
------ --------- -------- ---------
1         370.0     37.3     332.7
2         740.0    116.8     623.2
3         740.0     30.4     709.6

Interface Admin  Oper       Power   Device              Class Max
--------- ------ ---------- ------- ------------------- ----- ----

Gi2/0/11  static on         30.0    Ieee PD             4     30.0

But on the AP still display 802.3af:

PID VID: WAP571-A-K9 V01
Serial Number: PSZ20371EUK
Base MAC Address: 00:A2:89:35:21:20
Firmware Version (Active Image): 1.0.1.9
Firmware MD5 Checksum (Active Image): 76c5104b0bea5b76d016493589be8081
Firmware Version (Non-active): 1.0.0.15
Firmware MD5 Checksum (Non-active): 4ec95330b3c25e62e3ae7c840896f0ec
Host Name: FNA-N-WAP06
System Uptime: 0 days, 0 hours, 9 minutes
System Time: Thu Apr 6 2017 08:41:53 EDT
Power Source: 802.3af PoE

Did anyone solved this problem? 

Thanks.

[ktonev]

Hello,

My name is Kristian and I am one of the engineers from Cisco Small Business.

Can you confirm if you are using both radios (2.4GHz and 5Ghz) or only one of them?

Regards,
Kris

[antonio1dente]

Hi Kristian,

Yes I am using both.

Regards.

[ktonev]

Hi Antonio,

I suggest opening a support ticket with us so an engineer can look into this issue and assist you further.

You can find our contact details here.

Regards,
Kris

[craig.namken]

I am having this issue with the same hardware mentioned above and also with a WAP571 and C3850. Did you find any resolutions to this issue?

[Honver Lam]

I am happy to report that the power feature called "2-event classification" has finally resolved this issue on my 3850s. I had to upgrade the 3850s to the 16.3.6 train to get this feature to show up because it was not there in 3.6. I believe other switches such as the 2960x have this feature too.

https://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst2960x/software/15-2_4_e/configurationguide/b_1524e_consolidated_2960x_cg/b_1524e_consolidated_2960x_cg_chapter_0111111.pdf

WAP571 appears to have a faulty design that supports hardware-based Two-Event Classification but not LLDP classification.

"When the PSE detects a connected PD, it will send a short voltage pulse to determine how much power the PD needs. Depending on how much current is drawn during this pulse, the PSE will classify the PD into one of classes 0-4 (or 0-3 for type 1 PSEs and PDs).

If a type 2 PSE classifies the connected PD into class 4 (PoE+ power), a second handshake is required. This is both to allow the PD to know that full 802.3at power is available, as well as to allow the PSE to confirm that a type 2 PD is actually connected to the port for safety reasons. Prior to this second handshake taking place, the PD and PSE will restrict power to 802.3af limits.

This second handshake can take one of two forms: a hardware-based Two-Event Classification or a software-based LLDP classification. Per the 802.3at standard, PSEs must support only one of these mechanisms. However, PDs must support both classification methods.

In the hardware-based two-event classification, the initial voltage pulse classification event is repeated. Once the PD passes the second classification event as a class 4 PD, it will be provided full class 4 802.3at power. This method was initially intended to be used by mid-span PoE injectors, as they generally will not support LLDP required for software-based classification.

For the software-based LLDP classification, LLDP must be enabled on both the PSE and PD, with the 802.3at TLVs enabled. This will allow the PSE and PD to negotiate power requirements via software, rather than the second classification pulse used in the hardware based method. This also allows power requirements to be dynamically negotiated, allowing a PSE's power budget to be better managed."