Loss of internet in fibre connected external classroom

[Bev]

We have a portacabin which has a small cabinet in it, this is connected by a fibre back to the main school.

 

The cabinet contains an HP ProCurve switch 2520G, which has the fibre coming in to it.

 

The portacabin has lost all internet, both ethernet and wifi, and I can no longer see the AP on the control panel.

 

I have tried rebooting the switch, and we get a connection for 30 seconds and then it drops again.

 

I assume if we get a brief connection then the fibre is ok? But I'm not a fibre expert.

Any suggestions on what to try, I am having issues getting an engineer out in a timely fashion.

 

thanks

Bev

[djm968]

How is the fibre connected to the switch? Make/Model of switch would be useful. It is probably plugged into a SFP port via a module, do you have another module you could try? Edited September 22, 2020 by djm968

[sted]

id guess one of the fibre conversion modules is fubar (i had loads of these fail when they were the external non sfp ones)

[Bev]

Is that the little gadget between the fibre and the switch? Is it easy enough to buy a new one, do you need to know what type?

 

Photos of switch

 

[Bev]

HP ProCurve switch 2520G

[sted]

sfp is the little module that plugs into the switch. the fun part if one has failed is working out which end it is (unless you have another switch you can borrow one from) if you are buying new ones just make sure to get ones with the right type of fibre connection on them and that are for that switch. it is also possible a switch has lost its config and turned off the sfp port again unlikely

[djm968]

Yes the fibre GBIC module is the device that the fibre is plugged into in the second photo, best option is to remove it and check the spec to ensure you get the correct one. Looks like this might be similar but best to check before you buy anything. https://www.broadbandbuyer.com/products/15622-broadbandbuyer-3p-j4858c/ Edited September 22, 2020 by djm968

[LeMarchand]

Are either of the lights next to the fibre port flashing?

 

I'd be tempted to check the fibre lead is seated properly at the 3 possible points if not.

[Bev]

OK, I have found these.

 

I will try reseating everything.

 

thank you for all your help.

Edited September 22, 2020 by Bev

[Bev]

If I reboot the switch, the lights on the fibre come on for about 2 or 3 minutes and then they go off. There is a connection for that time but then it drops when the light goes off.

[3s-gtech]

Good news is that those modules have a lifetime warranty, if they’re faulty. I’d not advertise the serial numbers though. Do you have any spare patch leads to try too? Easy enough for these to get smooshed by a cabinet door.

[psydii]

Just checking its not spanning-tree? on the switches at either end of the fibre, type

 

show spanning-tree bpdu-protection PORTLIST

 

See what state your uplink ports are in.