Port Off as Underload Detected

[yoonie2]

Hello, I came across a network system that used 3 OmniSwitch 6450 PoE switches.
The customer came across a problem that shut down their network.
The customer then proceeded to pull out all the cables and connect them all again which miraculously seemed to get rid of the problem.
I was asked to track down what the problem was.
When I used show log swlog to see what was wrong, I noticed that the ports were shut down due to an "Underload Detected".
I haven't seen this error before, what would this usually mean?



LANPOWER info Port 1/3 turned OFF/Port Off as Underload Detected (10)

[silvio]

Hi,
in the KB there is one entry for this:
Non-PD connected ports show "Fault CAPDE" error (at command "show lanpower 1")
Analysis
Fault CAPDE error means the out of range capacitor value is detected by the PoE controller of the switch. Hence, the lanpower of the port is disabled.
...
Deny => Power Manager Algorithms have denied the power to this channel either due to priority disconnect or oversubscription.
Denied UDL: - Port is off, underload state according to 802.3af (current is below Imin).
...
Fault => Activation or class detection has failed, or an active channel has violated a boundary parameter.
Fault UD/OV: - Port is off, the succession of Underload and Overload states caused port shutdown. Maybe also caused by a PD’s DC/DC fault.
....
Note: It is recommended to turn on lanpower only on the ports where Powered Devices are connected to avoid these errors.

best regards
Silvio

[thermseeker]

Hello there,

Is there a way to configure the switch to disable the underload detection? I havent' found anything about that in the manuals. I have IP phones that are being denied power with "Denied UDL" status.

Thanks,
Tales

[thermseeker]

The same phones that in some cases get "Denied UDL" are now also showing "Fault CAPDE". What a piece of garbage. They are ATCOM D38 phones, steer clear of those. I have 20 units to get rid of.