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ConnectX is mlx4 (Ethernet/InfiniBand) for ConnectX-3, or mlx5 for ConnectX-4 and above.

Connect-IB is mlx5 (Infiniband only).

Setting Ethernet mode in the firmware

The default link protocol for at least ConnectX-4 is Infiniband. Changing this requires mlxconfig from the MLNX_OFED package's mft deb. mlxconfig requires mft to be running (which requires the mst_pci kernel module); /dev/mst will be populated once this has happened. This device is in Infiniband mode:

[strangelet](0) $ sudo mlxconfig -d /dev/mst/mt4115_pciconf0 query | grep LINK_TYPE
         LINK_TYPE_P1                                IB(1)           
[strangelet](0) $ 

...and here we change it to Ethernet (type 2):

[strangelet](0) $ sudo mlxconfig -d /dev/mst/mt4115_pciconf0 set LINK_TYPE_P1=2 

Device #1:

Device type:    ConnectX4       
Name:           N/A             
Description:    N/A             
Device:         /dev/mst/mt4115_pciconf0

Configurations:                                      Next Boot       New
         LINK_TYPE_P1                                IB(1)           ETH(2)          

 Apply new Configuration? (y/n) [n] : y
Applying... Done!
-I- Please reboot machine to load new configurations.
[strangelet](0) $ 

See also