Device won't turn on via PoE. Link up, link down, link up, etc.

[PatrickG_SF]

Hi all, 

I have a device made by a manufacturer called Crestron that takes PoE plus. I have a pair Catalyst 3850s with stacking cable, and quite a few PoE devices on it, all of them 15.4W, but still far within my PoE budget. My issues is, when I plug in 2 Crestron device, I get console feedback 'link is up', 'link is down', etc. I get so much chatter that it is hard to debug what is going on without unplugging it. I have LLDP enabled and CDR disabled, and no luck. I have noticed a few odd things:

- When I run a test cable diagnostic, I get a reported short on 2 pairs. This happened with 3 different cables, on 2 different devices. One of these cables, I was able to power the device with an unmanaged switch and there were no apparent issues.

- I have seen the switch report 'power granted' for the respective interface, but no connectivity.

- As mentioned, I have an unmanaged Ubiquiti PoE+ switch and the unit fires up fine with 0 issues.

Any help is appreciated here. Also,

- Here is a snippet of the console when I run a debug ilpower powerman command: 

BMR-GOP(config-if)#
*Oct 28 22:13:56.038: %ILPOWER-5-IEEE_DISCONNECT: Interface Gi1/0/1: PD removed
*Oct 28 22:13:56.955: %ILPOWER-7-DETECT: Interface Gi1/0/1: Power Device detected: IEEE PD
*Oct 28 22:13:56.955: (Gi1/0/1) data power pool 1
*Oct 28 22:13:56.955: Ilpower PD device 3 class 7 from interface (Gi1/0/1)
*Oct 28 22:13:56.955: (Gi1/0/1) state auto
*Oct 28 22:13:56.955: (Gi1/0/1) data power pool: 1, pool 1
*Oct 28 22:13:56.955: (Gi1/0/1) curr pwr usage 30800
*Oct 28 22:13:56.956: (Gi1/0/1) req pwr 15400
*Oct 28 22:13:56.956: (Gi1/0/1) total pwr 405000
*Oct 28 22:13:56.956: (Gi1/0/1) power_status OK
*Oct 28 22:13:56.956: ilpower new power from pd discovery Gi1/0/1, power_status ok
*Oct 28 22:13:56.956: Ilpower interface (Gi1/0/1) power status change, allocated power 15400
*Oct 28 22:13:56.956: ilpower_notify_lldp_tlv: lldp power class tlv:shut
BMR-GOP(config-if)#
*Oct 28 22:13:56.956: (curr/prev) pwr value 15400/0
*Oct 28 22:13:56.958: ilpower_notify_lldp_power_via_mdi_tlv Gi1/0/1 pwr alloc 15400
*Oct 28 22:13:56.958: Gi1/0/1 AUTO PORT PWR Alloc 130 Request 130
*Oct 28 22:13:56.958: Gi1/0/1: LLDP NOTIFY TLV:
(curr/prev) PSE Allocation: 13000/0
(curr/prev) PD Request : 13000/0
(curr/prev) PD Class : Class 4/
(curr/prev) PD Priority : low/unknown
(curr/prev) Power Type : Type 2 PSE/Type 2 PSE
(curr/prev) mdi_pwr_support: 7/0
(curr/prev Power Pair) : Signal/
(curr/prev) PSE Pwr Source : Primary/Unknown
*Oct 28 22:13:57.653: ilpower delete power from pd linkdown Gi1/0/1
*Oct 28 22:13:57.653: Ilpower interface (Gi1/0/1), delete allocated power 15400
*Oct 28 22:13:57.653: Ilpower interface (Gi1/0/1) setting ICUT_OFF threshold to 0.
*Oct 28 22:13:57.653: ilpower_notify_lldp_power_via_mdi_tlv Gi1/0/1 pwr alloc 0
*Oct 28 22:13:57.653: Gi1/0/1 AUTO PORT PWR Alloc 130 Request 130
*Oct 28 22:13:57.654: Gi1/0/1: LLDP NOTIFY TLV:
(curr/prev) PSE Allocation: 13000/0
(curr/prev) PD Request : 13000/0
(curr/prev) PD Class : Class 4/
(curr/prev) PD Priority : low/unknown
(curr/prev) Power Type : Type 2 PSE/Type 2 PSE
(curr/prev) mdi_pwr_support: 7/0
(curr/prev Power Pair) : Signal/
(curr/prev) PSE Pwr Source : Primary/Unknown
*Oct 28 22:13:57.654: ilpower_notify_lldp_tlv: lldp power class tlv:
*Oct 28 22:13:57.654: (curr/prev) pwr value 15400/0
*Oct 28 22:13:59.659: %LINK-5-CHANGED: Interface GigabitEthernet1/0/1, changed state to administratively downAllocAlloc
^

[Leo Laohoo]

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@PatrickG_SF wrote:
I would like to think its a hardware failure, but I cannot be sure. 

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Right now, I still am unable to determine if this is a client issue, a cable issue, hardware issue or a plain-and-simple software bug.  

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@PatrickG_SF wrote:
When I examine the ilpower debug that I posted at the top of the thread it appears the device is requesting 15400W

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That is normal.  This is how PoE logic works: 

1. A powered device (PD) is plugged into a port. 
2. Because the switch has PoE enabled to the port, how does the switch know if the connection at the far end is a PD or not?  By providing power to it.  But at what rate?  Obviously, 15400w.  
3. Whether the PD requires 15.4w or not, because power is being provided starts to boot up. 
4. PD three methods to negotiate power:  CDP, LLDP or none.  
5. IF the PD does not support CDP or LLDP, the switchport will give it 15.4w.  This is "acceptable".  
6. If the PD supports CDP or LLDP, the PD will talk to the port and negotiate the power draw.  

Right now, the easiest thing to do is to plug a known- and working PD into the ports to eliminate as much "suspects" as possible.