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Link Flap errors

Level 1
Level 1

We are seeing some "interesting" issues. We installed a pair of Nexus 7000's for our core and upgarded our distribution 4507s to 4507 R+Es.

These are connected over 62.5 fiber using Ciscos 10G-LRMs. What I am seeing is link flap errors, but ONLY on the Nexus side. There are CRC & input errors. When looking at the 4507, the links are clean, NO errors.

This leads me to believe there are differant thresholds on the Nx 7000!

Any thoughts?


4 Replies 4

Gregory Snipes
Level 4
Level 4

Are you using the proper mode conditioning patch cords with these? 10Gig-LRMs require them to work properly over 62.5 micron (FDDI grade) fiber optics.

All of my patch cords are 62.5 / 125 MM rated. I have no mixed diameters.

The 10G-LRM optics require a mode conditioning patch cord for use with 62.5 micron fiber. They do not require one if you are using 50 micron OM3 or OM4 fiber. This is noted on the datasheet but more detail is available here. This is very likely the cause of your errors and link flap.

Gregory, thanks for the input. I will order a couple of patches and see if that does fix my issue.

Again, thanks!

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