port reset due to power error

[suthomas1]

Hi,

we see the error below on our 3650 switch.
it occurs sometimes, the port gets connected up by itself after a while.

Power availability looks ok per the inline power output.

an access point is connected to this port.

Please help with this.

%ILPOWER-5-IEEE_DISCONNECT: Interface Gi1/0/21: PD removed
%ILPOWER-3-CONTROLLER_PORT_ERR: Controller port error, Interface Gi1/0/21: Power Controller reports power Imax error detected
%ILPOWER-5-IEEE_DISCONNECT: Interface Gi1/0/21: PD removed

Module Available Used Remaining
(Watts) (Watts) (Watts)
------ --------- -------- ---------
1 780.0 251.4 528.6

[Leo Laohoo]

Is the downstream a powered device or not?
If it is, check the port to make sure the cable isn't faulty. (Do a TDR.)
If it is not, then disable PoE. Check the IOS, this is a known bug.

[suthomas1]

Thanks, yes the downstream device is powered by Poe. 

We haven’t done cable check, but moved it to another port but shows the outcome/error. 

If this is cable related, then should this not be staying down all the while & not give that error? In this  case it is intermittent.

Please help. 

[Leo Laohoo]

Run a TDR on the link to see if there is a cable fault. 

[Georg Pauwen]

Hello,

in addition to Leo's post, check if your IOS supports the command below:

Switch(config)# int GigabitEthernet1/0/21 
Switch(config-if)# power inline port 2x-mode
Switch(config-if)# shut
Switch(config-if)# no shut

[jalejand]

What IOS version are you using ? Post a "show mod"

Is this the only device affected by the Imax error?

Does this happen on a different port?

In Imax error (or Current max) happens when a class is negotiated between the end device and the switch, if the end device is drawing more energy than the maximum configured for its class, it will exceed a current value, causing the port to be shut due to an "Imax" error.

Try statically allocating more available power on the port you are having issues with first.

interface GigabitEthernet1/0/21
  power inline static max 40000

For Imax errors, it is hard to determine the exact cause. In almost all cases these are found to be an issue with the PD drawing more power and the PD vendor needs to be engaged in order to investigate why it exceeds the power it has negotiated with the switch.