Hello,
can I somehow establish a connection between a router with an SFP port (e.g. Hex PoE or RB3011UiAS-RM) and an SFP+ port on a switch (e.g. CRS326-24G-2S+RM or CRS328-24P-4S+RM) ?
Lars
Depends on what type your SFP+ is. Copper ones are often multi-rate and will do 1G. Optics not so much. Putting an SFP in your switch is probably the easiest.
So an SFP module will work in the SFP+ cage of the above mentioned switch?
Lars
Yes, they will. You can look at the SFP compatibility list to be sure.
And when it is a local connection you can consider a DAC cable, but also after checking compatibility. I think with a RB3011 there are problems with that.
4011s too (they don’t support passive DACs)
Great, thanks for answers, these help a lot!
Lars
Can a CRS309 switch be connected to a CRS125 via the SFP+ and SFP ports, respectively, using a Cable Matters 10GBASE-CU DAC Twinax cable? I tried it myself, but couldn’t get it to work. I was able to set the CRS309 SFP+ port’s link speed to 1GB, which got me some link lights, transmit activity, and “link up” status. But, nothing on the receive side at all. I got nothing on the CRS125 switch at all. No link lights on the SFP port and a “no link” status in the web interface. I contacted the Cable Matter Rep and he said that it should work, but that I should check with Microtik to confirm the compatibility of these two switches connecting together like that. Any help will be greatly appreciated.
Yo! I tried to connect SFP (RB2011UiAS-2HnD-IN) to SFP+(CRS305-1G-4S-IN) with EDGE 10G-SFP-300-MT SFP+ transceiver. I see it in RB2011UiAS-2HnD-IN but the connection does not work.
Isn’t compatible?
SFP+ module in SFP cage (RB2011) won’t work. SFP module in SFP+ cage should.
Yes, you need to use SFP materials. Not SFP+ in SFP mode, I think not even that would work.
And also not a SFP module at one end connected via fiber to an SFP+ module at the other end, that likely also won’t work.
That is actually not exactly true. I was curious about it so I made a quick test:
CRS328 (sfp-sfplus4 cage) —> SFP1G-SX-85 —> om4 —> SFP-10GSR-85 —> CRS354 (sfp-sfpplus4 cage)
It didn’t work straight away though - because SFP does not have autonegotiation, I had to disable it in in the CRS354 and force the 10Gbit sfp+ module to run only 1Gbit. Then it established a link.
There are several compatibility breaks which has to be considered:
- cage vs module: SFP+ cages are often backwards compatible with SFP modules. However not the other way (plugging SFP+ module into SFP cage will likely not work). 10G/1G Backwards compatibility notes for mikrotik products are here: https://wiki.mikrotik.com/wiki/MikroTik_wired_interface_compatibility#SFP.2B_interface_compatibility_with_1G_optical_transceivers
- wavelength: Obviously, both modules must have the same wavelength. If one is 850nm and other is 1310nm, it won’t work.
- speed: Obviously, rate of the link will be limited to slowest of both modules. I can’t guarantee that every 10G module will support forced 1G rate so it may not work with all modules on the market.
SFP+ module in SFP cage (RB2011) won’t work. SFP module in SFP+ cage should.
The last works definitely fine ! (First can never technicallywise cause a physical 1G port can never ever work with 10G 
)
Keep in mind that the majority of 1G SFP modules do NOT do any autonegotiation in the SFP+ (10G) cage !
So using an SFP moule in the SFP+ cage often requires to set the port speed (interface setup) manually to a fixed rate of 1000Mbit. That brings 99.9% of all SFP modules (and DAC/Twinax cables) instantly to work !
Mikrotik is also NOT doing any SFP vendor checking. That means you can use every vendor branded SFP (and SFP+) modules in their products wuthout any issues ! Even BiDi SFPs (single stranded fiber) work just fine. 