SFP/SFP+ confuzion

Hmmm… Im confuzed.. I admit I have not done this before..

I plugged a SFP module into a CCR1036 SFP+ port.. This does not work. Well the router sees the module. Its sees the signal levels. It transmitts data… BUT the SFP only switch on the other end does not link..

I would think if I use a SFP module on both ends it should work ?

Is this some stupid issue I don’t know about ? Like you can’t plug a SFP device into a SFP+ devices even if you use SFP modules ?

This may sound dumb but you might have to swap fiber pair ends. Change the A to B and B to A.

Oh really ? Hmmm, never considered that. No wait, I don’t think that is the issue because on the Mikrotik side it shows a signal level for transmit AND rcv. If they were backwards, there would be no signal on on eof them right ? Also the module seems to show its hooked up. It shows link OK.. I have now tried 3 different brands of SFP modules. It all works when plugged into a SFP switch CRS112-8P-4S-IN

SO If i simply unplug the module from the CRS and plug into the CCR SFP+ port it does not work no matter what I do.
issue.gif

The CCR shows the link as OK, bu the device on the other end does not link. No data flows even tho the CCR attempts to send data..


issue2.gif

I think you have to disable auto negotiation and set the speed to 1000 full duplex on both ends in this case.

^^ yeah you’ll have to set speeds on both sides and I’d be checking the other device if yout Tik says the link is OK but is clearly not OK.

If your switch has more than one SFP port, try plugging both in there and see what it thinks. That way you’re checking both SFPs and the cable.

It is possible that SFP module is simply not compatible with CCR. Mikrotik’s SFP compatibility matrix indicates that even some Mikrotik’s own SFP modules are not compatible with all Mikrotik devices, so I’d expect third party modules to be even less compatible.

I have 6 different manufacturers of SFP modules I have now tried. These ALL work with a Mikrotik SFP switch. I did try the second SFP+ port.. I will look at this more today.

The strange part is the SFP modules and switch work fine when connected to a CRS with SFP ports but does not work when connected to the CCR.

I will investigate further..

So does anyone know for sure that a SFP module plugged into the CCR SFP+ port works ? I am just making sure.

That was it !!! Turned off auto-negotiate on the CCR and it worked immd… No need to change anything on the switch.. Just the CCR.

Also ALL my SFP modules for all 6 makers all work..

Well I learned something today…

Thank you :slight_smile: