mlxconfig set fails with "-E- Parameter ' value is smaller than minimum allowed 1"

Hi Mellanox community,

I have problems setting the NUM_OF_VFS on my ConnectX-4 Ethernet adapter (MCX416A-BCAT).

I want to use mlxconfig to set NUM_OF_VFS, but regardless if I try it under ESXi 6.5 (mft- or Windows Server 2016 (WinMFT_x64_4_8_0_26.exe) I get the same error.

Here’s what I’m trying (following HowTo Configure SR-IOV for ConnectX-4 with ESX 5.5/6.0 Native (Ethernet) ):

[root@localhost:~] /opt/mellanox/bin/mlxconfig -d mt4115_pciconf0 set NUM_OF_VFS=8

Device #1:


Device type: ConnectX4

PCI device: mt4115_pciconf0

Configurations: Next Boot New


Apply new Configuration? ? (y/n) [n] : y

Applying… Failed!

-E- Parameter ’ value is smaller than minimum allowed 1


I would be happy if anybody could comment or try the same on his/her ESXi/Windows machines.

The funny thing is that I once managed to set SRIOV_EN to true and NUM_OF_VFS to 4, but I don’t remember how I did that.

Thank you and best regards


Hi Axel,

  1. Update to the latest version of the firmware of MCX416A-BCAT 12.21.2010:

  1. Power cycle the server and run “mlxconfig -d reset”

  2. Try again to set the VF size .



Hi Samer,

it was the “mlxconfig -d reset” which did the trick. So I guess there was a f… up in the configuration and the reset cleaned it.

Thank you very much!


Hi Samer,

thanks for your reply.

The card has the latest firmware:

[root@localhost:/opt/mellanox] ./bin/flint -d mt4115_pciconf0 -i fw-ConnectX4-rel-12_21_2010-MCX416A-BCA_Ax-FlexBoot-3.5.305.bin burn

Current FW version on flash: 12.21.2010

New FW version: 12.21.2010

Note: The new FW version is the same as the current FW version on flash.

Do you want to continue ? (y/n) [n] :

It must be something else.