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3750 POE Port Status LED solid amber/Status link off, self resetting

I am an independent security contractor working with a Cisco 3750-48PS and Trendnet TW-715 wireless access point setup. I have no access at this time to view any diagnotics of the switch in question and am trying to determine if the fault occuring is due to my eqipment and its POE operation, the Cisco POE or some other aspect of port security. The equipment manufacturer states it is not compatible with IEEE 802.3a and as such provided a passive inline POE injector to power the unit with 12VDC.Connecting direct to my laptop I can establish communications to my security panel on the other side of the wireless link. Once I connect this cable into the customer's 3750 the status link light illuminates only briefly and then goes out. Selecting the POE port status shows the port lit solid amber. If I disconnect the equipment, eventually the amber LED goes out. I can then plug in any other computer on the network (not POE) and establish a proper link light and get connectivity. This implies to me that the port has not failed but is being shut down for some other reason. I am trying to determine if this is an issue of switch management with respect to the IPs I may have assigned to my equipment. I was told that there should be no issues if I grab a suitable IP and assign it statically from within the proper subnet. Or is it more likely a case that the port is either seeing some sort of voltage on the line it does not like or is unable to perform the proper negotiations with this other manufacturer's equipment due to the incompatibility with the standard. I have even tried placing a smaller switch ahead of the Cisco unit to try and isolate the two pieces of equipment. Once again, as soon as that smaller switch which has the upstream POE gear connected is plugged in to the 3750 the port does not allow connectivity. I am subcontracted for work and will have to contact the company's network guy to get any sort of information that is obtained from CLI troubleshooting on the switch.Thanks to anyone who can help with my issue.

 

*Just to clarify when I refer to any LED it is with respect to the specific port on the switch, not the actual POE led on the far left of the unit. So I plug my gear into port 43, it is unresponsive, goes blank for status, amber for POE. Unplug, wait for rest then plug in a PC to the very same port and things work fine.

1 REPLY

Hey,Looks like some issue

Hey,

Looks like some issue with PoE daughter card on PS unit so i believe best way to confirm is collecting show log, show post and show power.

HTH.

Regards.,

RS.

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