[c-nsp] Strange X2 Temperature Flaps

[sthaug at nethelp.no]

> Within 48 hours we have had three very strange issues with three different X2 modules, installed in 2 different chassis (both in 6708-10G/Sup720/6509E). In each case, the module's temperature reading has jumped and then oscillated from +127C to -127C over the course of the next 5 hours.
> 
> Each time it completes a loop it jumps from -127 to +127 - at _that_ moment we get a short burst of CRC errors in the ASR9k which is connected to the other end of the link. In two of the cases so far, the errors were enough to trip OAM on the ASR9k into err-disable on the port due to >3 seconds of symbol errors.

This problem (temp looping through all values) has also been observed
on third party 10G XFPs for Juniper routers. We got the XFP vendor to
replace the XFPs. Problem solved.

Steinar Haug, Nethelp consulting, sthaug at nethelp.no