I found some interesting issues today when interconnecting MikroTik SFP and SFP+ ports.  If you put a 10G module in an SFP+ cage and link it to another 10G module, there are no issues.  Same thing with 1G modules but when you start mixing SFP+ cages with SFP modules things get strange. Strange in that sometimes it works and sometimes it doesn’t.

Example:

• CCR1016-12S-1S+: SFP+1 interface works only in 10G link rates.
• CCR1032-8G-2S+: both SFP+ interfaces can work in 10G and 1G link rates.
• CRS226: SFP+1 interface can work both with 10G and 1G link rates, but SFP+2 is locked to 10G link rate.

These restrictions come due to certain hardware design limitations according to Krisjanis, a MikroTik engineer.  Here is a chart that covers a few of these combinations and capabilities:

• NOTES:
  • CCR1009-8G-1S-1S+ — SFP+1 interface does not support rj45 SFP modules. SFP1 interface however will work just fine with this type of transceiver.
  • CCR1016-12S-1S+ / CRS212-1G-10S-1S+ — SFP+1 interface does not work on any other link speed than 10G.
  • CRS226 / CRS210 — Only SFP+1 interface supports SFP 1.25G fiber optic transceivers, SFP+2 works only with 10G transceivers/links.

One other thing I learned is that many 0G transceivers will link to 1G devices if you set them both to auto negotiation off.  Good luck with MikroTik SFP’s!