I came out with a little issue.
I have a CISCO SF102-24 with MGBSX1 SFP
and a CISCO Catalyst 2960x with GLC-SX-MMD SFP
There is a 100m multimode fiber between them with 4 fiber cables , so I have two available connections if by any means one goes down.
The problem is that I have no link between them, as the SF102-24 switch is unmanaged I can't do anything to it, but I am thinking that maybe on the 2960X there is an option that I must put in order for the link to go up.
I have the latest firmware on the 2960x also. And the config looks like this: