Cisco 2960-CX POE flickering for Class 0 POE devices

[maxwell crowe]

Hi, i have two different 2960-CX switches that have been exhibiting wierd issues - attaching FLIR A500F cameras or A310 cameras to the switch, the switch won't provide POE power to these devices, the ports will flicker on and off POE power. if i attach an injector between the switch and camera, everything works as normal. the switch POE is not overloaded, the log shows no information about the flickering, and the power inline report seems to be correctly negotiating the class 0 POE requirement. 

class 2 devices (FLIR AX8 cameras) are being powered correctly on the same switch

[marce1000]

 - Following this link https://movitherm.com/wp-content/uploads/2021/06/A500F-A700F-Datasheet.pdf , it seems to be  IEEE 802.3af class 3 based. From https://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst2960x/software/15-0_2_EX/int_hw_components/configuration_guide/b_int_152ex_2960-x_cg/b_int_152ex_2960-x_cg_chapter_0111.html : 

 >..The initial allocation for Class 0, Class 3, and Class 4 powered devices is 15.4 W. When a device starts up and uses CDP or LLDP to send a request for more than 15.4 W, it can be allocated up to the maximum of 30 W.

   If it does not understand  CDP or LLDP then you may need to set port inline power to max (30W)

 M.

[maxwell crowe]

i went ahead and tried some things with what you said in mind, i'm not sure how i can view or diagnose the CDP or LLDP communication, but i did modify the maximum power for one of the ports, Gi0/2 in this case. i used the commands -

config t

interface Gi0/2

power inline consumption 30000

after applying those commands, i now see the port trying to use all 30W of power, which is interesting considering the port should have already been configured to use that much. however, even with this change in power usage the port doesn't stay up for more than half a second. 

below is a screenshot of the CLI, highlighting port Gi0/2 with it's increased power limit, Gi0/6 has the same model of camera attached with completely default POE settings

if i run show power inline in rapid succession, i can see the POE cycling on and off for these ports, this screenshot is just a snapshot of when both ports were up at the same time

thanks for replying, marce1000

[marce1000]

 - No immediate further insights , but it is always advisable to use the latest software version on the 2960-CX   https://software.cisco.com/download/home/286282780/type/280805680/release/15.2.7E5 , to avoid issues related to bugs (potentially)

 M.