RJ45 SFP+ Overheat

Hello!

I have a mikrotik switch (CRS309-1G-8S+IN) that i bought 2 days ago. I have some dac patch cords connected and 2 RJ45 SFP+ with cat 6a patch cords. When I start network traffic on the RJ45 SFP connectors, they overheat to 95 degrees celsius and the switch turna them off. I don’t have the same problem with the fiber dac patches. There is room in the server room between the switches, there is space between the rj45 connectors, the server room is temperature controlled, with AC running non stop on 19 degrees.

http://forum.mikrotik.com/t/sfp-sfpplus1-high-temperature-warning/181439/6

Adding cable and module part numbers may improve feedback on this topic.
MikroTik is clear their RJ45 module has limits S-RJ10 general guidance

S+RJ10 is extremely power hungry - 2.4W over 30m.

If you want really need RJ45, you are better off buying 10GBaseT modules that use the newer Broadcom chipsets - you can identify them by the max distance they support, which is either 80m or 100m over Cat6A and consume less than 2W at those distances.

  1. 80m with temp sensor but not NBaseT
  2. 100m without temp sensor but with NBaseT

Thanks for sharing this issue—I’m facing something similar with WireGuard and routing. Your post and the replies helped me realize I might’ve missed a firewall or NAT rule. MikroTik setups can be tricky, but posts like this really help newbies like me learn and fix things faster. Much appreciated! If you’re overwhelmed with assignments or tight on deadlines, using an essays writing service from https://domypaper.com/ can be a smart solution. DoMyPaper offer expert help and deliver high-quality, plagiarism-free work tailored to your needs. It’s a practical way to manage time effectively and stay on track academically.