4900M with X2-10GB-SR threshold errors

[arthurlove]

Hi

I have 2 4900M connected together via a port-channel using 2 tengbe interfaces. The swtiches are right next to each other. The fiber patch leads are new.

I am getting the following errors on both swithes [16 interfaces tried]:

*May  4 10:57:13.191: %SFF8472-5-THRESHOLD_VIOLATION: Te1/1: Rx power low warning; Operating value: -13.7 dBm, Threshold value:  -9.9 dBm.
*May  4 10:57:15.191: %SFF8472-5-THRESHOLD_VIOLATION: Te1/3: Rx power low alarm; Operating value: -14.6 dBm, Threshold value: -13.9 dBm.$HRESHOLD_VIOLATION: Te1/1: Rx power low warning;

The port-channel then unbundles and sometimes the offending interface re-joins. I have placed another interface [te 1/8] into the port channel and this seems to stay up

sh ver and sh transiever outputs below

sh interfaces tenGigabitEthernet 1/1 transceiver detail
ITU Channel not available (Wavelength not available),
Transceiver is internally calibrated.
mA: milliamperes, dBm: decibels (milliwatts), NA or N/A: not applicable.
++ : high alarm, +  : high warning, -  : low warning, -- : low alarm.
A2D readouts (if they differ), are reported in parentheses.
The threshold values are calibrated.

                              High Alarm  High Warn  Low Warn   Low Alarm
          Temperature         Threshold   Threshold  Threshold  Threshold
Port       (Celsius)          (Celsius)   (Celsius)  (Celsius)  (Celsius)
--------- ------------------  ----------  ---------  ---------  ---------
Te1/1       28.1                74.0        70.0         0.0       -4.0

                              High Alarm  High Warn  Low Warn   Low Alarm
           Voltage            Threshold   Threshold  Threshold  Threshold
Port       (Volts)            (Volts)     (Volts)    (Volts)    (Volts)
---------  ---------------    ----------  ---------  ---------  ---------
Te1/1      3.25                   N/A         N/A         N/A        N/A

           Optical            High Alarm  High Warn  Low Warn   Low Alarm
           Transmit Power     Threshold   Threshold  Threshold  Threshold
Port       (dBm)              (dBm)       (dBm)      (dBm)      (dBm)
---------  -----------------  ----------  ---------  ---------  ---------
Te1/1       -2.4                 2.9        -1.0        -7.3      -11.3

           Optical            High Alarm  High Warn  Low Warn   Low Alarm
           Receive Power      Threshold   Threshold  Threshold  Threshold
Port       (dBm)              (dBm)       (dBm)      (dBm)      (dBm)
-------    -----------------  ----------  ---------  ---------  ---------
Te1/1      -13.6                 2.9        -1.0        -9.9      -13.9

sh ver
Cisco IOS Software, Catalyst 4500 L3 Switch Software (cat4500e-IPBASEK9-M), Version 12.2(54)SG1, RELEASE SOFTWARE (fc1)
Image text-base: 0x10000000, data-base: 0x12C41C68

ROM: 12.2(44r)SG5
Sushi Revision 11, Tatooine Revision 141, Forerunner Revision 1.78

uptime is 30 minutes
System returned to ROM by power-on
System image file is "bootflash:cat4500e-ipbasek9-mz.122-54.SG1.bin"

WS-C4900M (MPC8548) processor (revision 2) with 524288K bytes of memory.
Processor board ID JAE14360LUF
MPC8548 CPU at 1.33GHz, Cisco Catalyst 4900M
Last reset from PowerUp
20 Virtual Ethernet interfaces
20 Gigabit Ethernet interfaces
8 Ten Gigabit Ethernet interfaces
511K bytes of non-volatile configuration memory.

Configuration register is 0x2101

I have seen issues like this before [and Q posted on forums] with the 3750 ..

ANy ideas

Thanks in advance

[Reza Sharifi]

Hi,

What type of Gbics and fiber are you using?

Is the fiber patch MM or SM and how about the Gbics?

It aperas that you have too many DB looses

Reza

[arthurlove]

Thanks for your interest..

Fibres are 2M SM - they come from a batch being used on other jobs - all working fine

GBICs are cisco X2-10GB-SR - i have swapped these around and get the same results

Operating conditions are good re; temp and humidity

[Reza Sharifi · Accepted solution]

since the switches are so close to each other, can you try using MM fiber with MM Gbic?

[arthurlove]

I am afraid that the only GBics I have are the x2-10 above - same applies to the fibre ....

Changing the GBICs would not be an option - we have 16 of them and they are NOT cheap !!

Why do you thing that changing to MM fibre woudl improve things

..again thanks for your interest here :-)

[arthurlove]

Cheers - that was it - managed to find some MM fibre with SC-SC. issues went away !!!

thansk

[Reza Sharifi]

Glad to help. Thanks for the update