I need to connect 3 switches via fiber....

[JeffRich38232]

I am using a SG350-28MP and 2 SG350-10MP. The SG350-28 is my main switch, the other 2 are in remote closets connected by fiber. I have the fiber modules and fiber connected but no action on remote closets. What configuration do I need to get them talking?

[Georg Pauwen]

Hello,

with compatible SFPs and the correct fiber cable, the links should come up. Which SFPs are you using, and what fiber (single/multi mode) ?

[JeffRich38232]

Single Mode Fiber and Single Mode SFP's. The SFP's are from Legrand that are supposed to be compatible.

[Reza Sharifi]

If the SFPs are compatible, check the cables/connectors to make sure they are fully inserted. Also, depending on if you are using patch panels, sometimes you need to switch the strands on one side of the connection to bring up the link. Usually, for physical layer connectivity (layer-1) you don't need any configuration on the ports but make sure the ports are not in shutdown states.

Also, if the SFPs are compatible, they should have a Cisco part number on them.

HTH

[Georg Pauwen]

What is the exact part number and/or product description ? The SG switches have a different architecture than the Catalyst switches, so check if any SG switches are explicitly mentioned in the list of compatible switches.

[paul driver]

Hello
In additional to others, you need to understand that sfps also come in two modes for distance, Long haul (LX) or Short haul (SX) so depending how far the closets are from each other would depend on what sfps you need to use.

Once you have the correct hardware then I am assuming you would want these switches to be attached together by a trunk interfaces unless you are not extending your Layer 2 across the links, in that case that can be be access-ports or even L3 routed ports

[JeffRich38232]

It also helps when the polarity of the patch cables is correct!