Insufficient PoE supplied from 5130

[MatMatMat]

Morning!

We have a problem whereby a Cisco CP-8851 phone + sidecar is unable to draw enough power from the 5130 it's attached to. The phone itself will power up (and work) but the sidecar wont. If I move the phone + sidecar to another 5130, which is configured exactly the same (as far as I can tell), it is fine; it can draw enough power for the phone and the sidecar.

Both units are 5130 48G PoE+ 4SFP+ but the main difference is that the 5130 having problems is in a stack of 4 whereas the working one is on its own.

Problem unit:
PSE ID : 13
Slot No. : 4
SSlot No. : 0
PSE Model : LSP7POEB
PSE Status : Enabled
Power Priority : Low
Current Power : 18.0 W
Average Power : 17.5 W
Peak Power : 22.0 W
Max Power : 370.0 W
Remaining Guaranteed Power : 370.0 W
PSE CPLD Version : -
PSE Software Version : 145
PSE Hardware Version : 57633
Legacy PD Detection : Disabled
Power Utilization Threshold : 80
PD Power Policy : Disabled
PD Disconnect-Detection Mode : DC

<switch->dis poe int GigabitEthernet 4/0/3
PoE Status : Enabled
Power Priority : Low
Oper : On
IEEE Class : 3
Detection Status : Delivering Power
Power Mode : Signal
Current Power : 3500 mW
Average Power : 3460 mW
Peak Power : 4500 mW
Max Power : 30000 mW
Electric Current : 67 mA
Voltage : 52.5 V
PD Description :
<switch->

It is supplying power, just not enough and none of the units in the stack are stressed with regards to supplying power.

The working unit is the same but when the sidecar comes on, the phone draws about 6000mW without any problems.

Is there any reason why a port would not allow enough juice to flow?

Many thanks

MMM

[VoIP-Buddy]

Mat,

What version of Comware are you running?

Do you have LLDP and perhaps CDP enabled?

As a check, you can configure the ports to supply power by using the poe max-power command.  What class phone is that?

David

[MatMatMat]

Both 5130s are running v7.1.045 - 3113P05 and both have lldp global and compliance cdp enabled.

I've had a play with the max-power however as the ports were already set to supply a max of 30000, I don't think that made any difference (there was no change in the amount of power being supplied via the port in question).

The phone is a class 3, af and at compatible, and the sidecar requires 117mA max (according to its tech sheet).

Many thanks

MMM

[parnassus]

What's about giving R3115P05 (end 2016) a try (clearly once a management window permits you to upgrade the entire IRF stack flawlessly)...at least a pair of PoE related issues [*] were solved between R3113P05 (mid 2016) and R3115P05...PoE Firmware is already at version 145 (on all IRF Members, right?)...so if the issue is going to (re)appear after R3115P05 is deployed...you will be able to infer that it is a Bug or, better, an Hardware issue related to one specific IRF member.

[*] I refer to:

• R3115P03 201609070269: "Symptom: PD detection and classification on a port are affected after PoE performs power negotiation on the port. Condition: None."
• R3115P03 201507220217: "Symptom: Maximum PI power negotiation fails on an interface configured with PoE. Condition: This symptom occurs if the maximum PI power is automatically deployed on the interface and the device is rebooted after the configuration is saved."

Also, which firmware the Cisco 8851 is currently running on?

[VoIP-Buddy]

I agree with Parnassus.  We have spent a lot of time with Cisco Phones and Comware switches.  It is important that the switch be at a recent version and the latest PoE firmware.  The fixes that were put in place are a package deal.  Having the latest PoE code with old Comware code doesn't give you the fix.  They must work together.

When it comes to PoE, always check the release notes to make sure that the PoE version is paired with the minimum Comware version as specified in the release notes.

If you have done that and it is still an issue.  Please open a support case so that we can investigate it further.

BTW... I would check to make sure that all of the IRF members have the latest PoE code and the correct Comware version.

David