Update! Got my hands on a Mikrotik S+RJ10 module and did some more testing. As indicated by @lawe, Flow Control is absolutely essential. 1G - problem resolved, wire speed in both directions. 2.5G - problem resolved, wire speed in both directions. 5G - nope. Issue unchanged. Module is reporting 5G sp...

I can confirm that the FS SFP-10G-T modules do not support NBase-T (2.5GBit/s and 5Gbit/s). It's quite weird - they sort of do. There's no problem negotiating a 2.5/5G link with the cards, but what they don't do is inform the CRS317 (or my QNAP QSW-M408S for that matter) that the link isn't anythin...

I have a CRS317-1G-16S+RM. It's running latest ROS and SwOS. SwOS is my default. Switch works great when running 10g fibre to various Mellanox cards with a few different SFP+ optics. I'd like to connect a few copper wired clients using 2.5g and 5g links. So I added a pair of fs.com "Cisco SFP-1...

Some devices are VERY picky about SFPs (HP switches come to mind - I know there are others). Very occasionally it's due to actual hardware and not just assholes in marketing... As my support ticket shows, even after buying the official Mikrotik SFP, the port still would not come up. Have you sent y...

My fs.com fiber modules and my active DAC cable still don’t function, but work on everything else. Can confirm Intel, Mellanox and Finisar 850nm SR modules working fine here. Well, fine as long as I'm NOT using Intel cards on the other end. Reading back and seeing you're using Mellanox CX3s, I'd be...

Hi Oliver, I had a longer conversation with Mikrotik support. They bought a bunch of Intel SFP modules: We ordered a bunch of them for us to fix this compatibility issue. We are not sure if we are going to be able to fix this so soon since we added compatibility to a different module and it seems t...

I can't test them further, because none of my cards really work with the CSS610, but the transceiver seems to work.

If you don't need to stick with the Intel x520's, Mellanox CX3's are a similar ebay price and work perfectly for me so far.

FWIW, my CSS610 has been recognizing and running well with
- Intel E10GSFPSR
- Mellanox MFM1T02A-SR
(these are both Finisar manufactured at a guess)
- FS.com NETGEAR AGM731F Compatible 1000BASE-SX SFP

The Intel optics can be had for maybe $10 USD each on the 'bay.

Same here, except a CSS610-8G-2S+IN SFP+ ports to Intel x520 card with Intel E10GSFPSR optics or FS DAC. Update After a couple of days, 1g autoneg between my x520 and the CSS610 stopped sorting out a connection. Had to force the card to 1g to get it linking again. Mellanox Connect-X 3 card arrived....

Same here, except a CSS610-8G-2S+IN SFP+ ports to Intel x520 card with Intel E10GSFPSR optics or FS DAC. Update After a couple of days, 1g autoneg between my x520 and the CSS610 stopped sorting out a connection. Had to force the card to 1g to get it linking again. Mellanox Connect-X 3 card arrived....

Same here, except a CSS610-8G-2S+IN SFP+ ports to Intel x520 card with Intel E10GSFPSR optics or FS DAC. SwOS v2.13 Switch reports 10g link, card says no. Forcing 1g at both ends gets link up. Swapping switch side optics for an FS.com 1g SFP delivers a 1g auto-negotiated connection. Swapping x520 ca...

connecting from my CSS610-8G-2S+IN SFP+ ports to Intel XXV710 based 25Gb NICs. Same here, except a CSS610-8G-2S+IN SFP+ ports to Intel x520 card with Intel E10GSFPSR optics or FS DAC. SwOS v2.13 Switch reports 10g link, card says no. Forcing 1g at both ends gets link up. Swapping switch side optics...