Cisco Fibre issue

[0x9h3]

Hello everyone,

 

I hope everyone had a good Christmas and New Year.

 

The fibre link to our upper school has gone down. These consist of Cisco 2960-s stacked, with 2 fibres apparently into the top 2 switches. I think the fiber connect LC (from memory)/ Although I think only 1 the fibre to top switch is working. I have tried reseating the connection both ends, I have used another module and connected the fibre to no avail. I have shown a light down the fiber and its only coming out of the one fibre cable.I have checked the core switches and there are no errors on there at all. Can anyone give me advise on what to try next? Does it sound like there's a break in the fibre cable?

 

Looking at the logs, it looks like it went down yesterday Sunday afternoon...

Any help greatly appreciated!

 

Thanks,

[FN-GM]

The trick you did with the light sounds like there is a physical break. Maybe rats or mice.

 

Probably time to get the experts in.

[FN-GM]

@0x9h3 - How did you get on?

[dylanm]

From the sounds of it, you have 4 cores (2 pairs). Using the light trick works nicely to see if there is a physical break in the fibre-optic cable.

 

Side note, there is a great tool on Amazon for visually checking fiber cores: https://amzn.eu/d/4KSIBrv

 

What you could do is check how many of the cores are broken. As long as you have a minimum of two cores working from either pair of fibres you can get away with taking a core from each fiber if that make sense?

 

This will get you up and running on the fiber temporary.

 

If you only have one core working out of the all of the cores then unfortunately, I think your out of luck.

 

We have a awesome cabling team that does our fiber and cable installations that I can get you in touch with (they are based in Essex but are pretty much national). They can run you a new fibers or re-splice the cable (if it is possible). PM me if you want more details.