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New Member


Hi All

I have a issue connecting my Cisco 3750X 12 port fibre switch to my Cisco 2960S 24Port switch using Multi Mode Fibre.

I have Mode condtioning cables connecting to the SFP (GLC-LH-SMD) on the 3750 via a fibre patch panel which bring me to the 2960s with its Mode conditioning cable and SFP (GLC-LH-SMD).

The fibre port on the Cisco 2960S was up for all of 10 mins and has gone out with the following error message.

%SFF8472-5-THRESHOLD_VIOLATION: Gi1/0/26: Rx power high warning; Operating value:  -2.7 dBm, Threshold value:  -3.0 dBm.

I did a show int transceiver command and got the following output.

DS-THN-SW3#show interfaces transceiver

If device is externally calibrated, only calibrated values are printed.

++ : high alarm, +  : high warning, -  : low warning, -- : low alarm.

NA or N/A: not applicable, Tx: transmit, Rx: receive.

mA: milliamperes, dBm: decibels (milliwatts).

                                 Optical   Optical

           Temperature  Voltage  Tx Power  Rx Power

Port       (Celsius)    (Volts)  (dBm)     (dBm)

---------  -----------  -------  --------  --------

Gi1/0/26     25.2       3.31      -5.1     -28.5

All SFP's are new as is the Multi Mode Fibre cable running from one building to another.

  • LAN Switching and Routing
Everyone's tags (8)
New Member

Hi All,One of  member port of

Hi All,

One of  member port of port channel was flapping and Here is the error message

Error log:

.Mar 17 08:27:37: %SFF8472-5-THRESHOLD_VIOLATION: Te6/1/1: Tx power low alarm; Operating value: -40.0 dBm, Threshold value: -11.3 dBm.

Cisco TAC analyse the issue under 629566213 but  their initial advices was not much experience oriented.

Finally I have resolved the issue just by entering following command.

switch 6 frulink reload

Janaka Wellege Bsc.Eng

University of Peradeniya.


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