Rx power low warning

[broow]

After upgrading the IOS of our Cat9500 to Version 16.12.4, we starting getting several Rx power low warnings:

Mar 9 09:27:39 EST: %SFF8472-3-THRESHOLD_VIOLATION: Twe2/0/1: Rx power low warning; Operating value: -10.3 dBm, Threshold value: -8.0 dBm.
Mar 9 09:35:26 EST: %SFF8472-3-THRESHOLD_VIOLATION: Twe1/0/1: Rx power low warning; Operating value: -8.6 dBm, Threshold value: -8.0 dBm.
Mar 9 09:35:26 EST: %SFF8472-3-THRESHOLD_VIOLATION: Twe1/0/2: Rx power low warning; Operating value: -11.0 dBm, Threshold value: -8.0 dBm.
Mar 9 09:35:56 EST: %SFF8472-3-THRESHOLD_VIOLATION: Twe2/0/3: Rx power low warning; Operating value: -8.5 dBm, Threshold value: -8.0 dBm.
Mar 9 09:35:56 EST: %SFF8472-3-THRESHOLD_VIOLATION: Twe2/0/4: Rx power low warning; Operating value: -10.1 dBm, Threshold value: -8.0 dBm.
Mar 9 09:37:39 EST: %SFF8472-3-THRESHOLD_VIOLATION: Twe2/0/1: Rx power low warning; Operating value: -10.3 dBm, Threshold value: -8.0 dBm

have cleaned, replaced fiber patch cords, replace SFP's, still no change.

Any ideas or suggestions?

[Reza Sharifi]

This is a cosmetic error message in the log of many Cisco platforms. If all your fiber connections are working fine and you don't see any error messages incrementing on the physical interface, you can ignore this message. If this message is coming from physical fiber interfaces that are not being used, simply shut them down.

HTH

[broow]

thanks,

is there a way to stop the messages from filling up the log file?

[Reza Sharifi · Accepted solution]

You can try the below command if you are logging in to buffer. 

no logging buffered errors

if not 

no logging console errors

should also help.

HTH

[Pyie Phyo Htay]

Hi Reza,

I'm also facing with this issues that i am configure C9300 switch 1 & 2 configure stacking mode. after that stack is running switch one is active and switch two is standby mode. 

Then we face that issues in console SFP power rx low warning. as you mention resolution is turn of the loggin console errors. I assume that is not the suitable resolution for this issue. Could you kindly please suggests for this.

Thanks in advance.

Pyie Phyo Htay.

[Spooster IT Services]

Hi,

We faced same errors with our Cisco 4500 series switch.
Here are the recomended steps to identify if this is an real issue or just a cosmetic bug

1. Check the interface status for any errors. If you have increment in errors on interface that may be the issue of either cable or with SFP/connector
(command to check "sh interface twe2/0/1")

2. confirm both of the transceivers are the same type (command to check "show inventory" )

3. confirm the transmit power of each transceiver (command to check "show interface transceiver detail").

4. confirm the tx/rx polarity of the connector.

5. Ignore these logs if you are not facing any issue. Bug Id CSCts58073 is one of the example of this type of cosmetic bug.

6. Shutdown all unused interfaces.

[broow]

thanks!

is there a way to stop the messages from filling up the log file?

[Tagir Temirgaliyev]

are u still receave messages after shutdown interfaces? its very strange

[engineer467]

Hello.

There isn't much difference in Transmit power of each transceiver, but I am seeing different values in Receive power, -8.2 on one, and -20.8 on another, after replacing the SFP module and fibre optic cable on switch where error logs were seen.

By the way, interface is still showing UP.

Now what should I try?

Please suggest.

Thanks in advance..