Using 100GbE to 4x25GbE breakout cables with ConnectX-5 EX NICs


We would like to use a 100GbE to 4x25GbE breakout cable where:

  • the 100GbE QSFP28 end goes to a Mellanox ConnectX-5 EX NIC on a PER640

  • the 4x 25GbE SFP28 ends go to a S5248F-ON switch

Could you point me to the relevant documentation, please?


Hello Sebastian,

Thank you for posting your question on the Mellanox Community.

Based on you request, unfortunately Mellanox adapters do not have the capability to split their ports.

Port-splits is always done from the switch side.

So you can split a 100GbE switch port into 4x25GbE to gain an additional 3 more ports to connect to end-point.

For example →–gt–4x10g-and-100g–gt–4x25g

Thank you,

~Mellanox Technical Support