ConnectX6-DX 100G configuration required to be used as 4x25G

Hello community!
Hopefully someone here can help me with my question. I am basically looking for the configuration required on the ConnectX6-DX NIC to change it from 1x100G Ethernet to 4x25G Ethernet. I have found information on how to do this on the switch here, but I was wondering how to do this on the server side NIC instead (if possible!).


NIC port cannot be physically splitted.

Thanks for your reply @dwaxman . Is there another NIC model from Nvidia/Mellanox that supports this feature? I know for a fact that Emulex/Broadcom have this kind of feature (break-out cable support) in some of their NICs because I used in the past.

Can you confirm @dwaxman, that the ConnectX cards do not support (eg, 4x25G) breakout cables?


The NICs do not support splitting physical lanes (unlike switch ports)

I’m not familiar with a usage scenario that requires a NIC port physically splitted to 4 ports.

Just for the thread completeness…
As advised in this thread, Mellanox NICs do not support it so we ended up using an Intel one that supports this:
Source: Ethernet Port Configuration Tool Infographic – Intel