alt Hacker NewsUnfortunately the blog didn't link to the SFP+ module they're using, but everyone should know there's effectively 2 different generations of 10gbit sfp+ to ethernet^H10BASE-T modules. The old gen, labeled as 30 meters, draws ~3 W, and gets extremely hot (to the point it'll usually cause link flaps), and the newer gen, usually labeled as 100m or 80m, draws ~1.5 W, and runs much, much cooler.
Example of the new gen: https://www.amazon.com/Wiitek-Transceiver-Compatible-UF-RJ45...
Old gen: https://www.amazon.com/10Gtek-SFP-10G-T-S-Compatible-10GBase...
Typically the old gen uses a Marvell AQR113C, and the new gen uses a Broadcom chip that I forget the number of off hand.
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This is the most important thing to know for anyone trying to do SFP+ to 10GBASE-T. It's too bad it wasn't covered in the article.
The thermal performance of the new modules is so much better that they'll make you want to throw away all of your old modules as soon as you try one. The old ones consumed a lot of power and put out a lot of heat. You can find examples of people adding active cooling to blow on them because they're so bad.
The new ones are great. They get warm but it's completely manageable. And the power draw is also closer to what the SFP+ ports on your device were probably designed to handle, so compatibility is better too.
BCM84891L. I like these modules (select 80 or 100 m in the drop down): https://www.luleey.com/product/10gbase-t-sfp-to-rj45-copper-...
Using this module, I was able to get a stable 10 gig over a 75 feet long, 20 year old run of Cat 5e.
I had this issue with old gen Unifi SFP+ to RJ45 10Gbe, 3 failed. Needed gloves to remove them. Bought newer gen and they are warm but i dont need gloves.
If you want to buy the cheaper old ones and are concerned about heat just add a usb fan. I have the same mikrotik switch in the post and 2 sfp to rj45 + this fan https://www.amazon.com/dp/B00G059G86?th=1 sitting on top and it makes a dramatic difference in temp.
Thanks! 10Gb Eth is insane for exactly this reason (optical SFP+ modules are way cheaper and more reliable)
I used to support a company that refused to run fibre, and had just run ethernet everywhere with the old 10GBE modules. Half their links were constantly flapping as the hardware powered off to cool down.
Even with the new modules, their ethernet cable runs were always in excess of what 10GBE could handle. I remember one at ~140 meters that was constantly renegotiating.
The worst part is, they had not a single element in their network that didnt support fibre. The fibre sfp modules for their radios was the same cost as the copper.
I love that these 10GBE modules exist but please (please please) just run fibre if you can.