[j-nsp] Power issues on 10Gig link

[Jared Mauch]

On Jan 23, 2014, at 8:14 AM, Ali Sumsam <ali+junipernsp at eintellego.net> wrote:

> Hi All,
> 
> I am using a SFP-10GBase-ER for my Cisco3750X for a 10gig link going to a
> Juniper MX5-T router (10GE XFP)
> 
> 
> I am receiving following logs on my Cisco3750X.
> 
> %SFF8472-5-THRESHOLD_VIOLATION: Te1/1/2: Rx power low alarm; Operating
> value: -21.3 dBm, Threshold value: -20.0 dBm.
> 
> No logs on Juniper.
> 
> Does this mean I have to increase the power on the interface?
> Or is there anything else I need to look at?
> 
> Following are the readings from my Juniper router.
> 
> Laser rx power high alarm threshold       :  1.2589 mW / 1.00 dBm
>    Laser rx power low alarm threshold        :  0.0158 mW / -18.01 dBm
>    Laser rx power high warning threshold     :  1.0000 mW / 0.00 dBm
>    Laser rx power low warning threshold      :  0.0199 mW / -17.01 dBm
> 

You need to take a look at your span length and OTDR numbers.

Was there recently a bend in the cable that caused this attenuation?

Do the light levels improve when cleaned?

If you replace the optic does the situation improve?

Is the launch power the same in both directions, but just low on the RX side facing the Cisco?

Finding the answers to these questions should resolve your alarms.

- Jared