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Fiber link issue

Hello,

I have a 3750 as my main switch in the MDF. I have a Fiber home run running from the MDF to one of my idfs that i would like to utilize as the trunk line.

Currently our fiber lines are running fine going from a 2950 MTRJ port to the SC ,out to the homerun into another SC patch, and then into an MTRJ port on another 2950.

I purchased a sfp (model #GLC-SX-MM) and i cant get a link up on that SFP. The fiber is multimode, 62.5 and so are the LC to SC patch cables we purchased.
I even tried hooking up a fiber cable from the 3750 sfp (LC) directly to a spare 2950 MTRJ port and no link there.
I have also switched cables in every possible send/rec combination.

Thanks,
Joey

from_exp

what about speed settings?
it is possible to test connectivity just pluggin only one fiber strand from tx into rx in the second switch. the rx'ed port should come up.
try setting both ports to speed 1000 duplex full.

joebass47

ASKER

Can you set speed settings on SFP ports?
If i try issue speed ? under that interface, it gives me the following:
fr_MDF_gig(config-if)#speed ?
nonegotiate Do not negotiate speed

I dont think it is possible to just connect one fiber strand because one of the switches is MTRJ which is send and rec in one port.

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from_exp

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joebass47

ASKER

I did that for the sfp port on the 3750, however, there is no speed option to configure speed under the 2950 mtrj ports.

joebass47

ASKER

I figured out what the problem was. I was under the impression that all of our switches at this location were 1000 base, unfortunately that wasnt the case, hince the mismatch.

Thanks,
Joey