Correct firmware for my CX354A-FCBT and ESXi 6.7U2 Compatibility Question

I have a server with what I do believe are two CX354A-FCBT adapters installed. However, trying to update the firmware using Windows Server 2019 I receive the following error message, which seems to be indicative of my having downloaded the wrong firmware. Does anyone know which firmware I should download instead?

C:\Program Files\Mellanox\WinMFT>mst status

MST devices:



C:\Program Files\Mellanox\WinMFT>flint -d mt4099_pci_cr0 -i fw-ConnectX3-rel-2_42_5000-MCX354A-FCB_A2-A5-FlexBoot-3.4.752.bin burn

Current FW version on flash: 2.33.5000

New FW version: 2.42.5000

-E- PSID mismatch. The PSID on flash (MT_1090110018) differs from the PSID in the given image (MT_1090120019).

Secondly, I understand that the ConnectX3 is not officially supported by ESXi 6.7U2. Will those cards work nonetheless on ESXi 6.7U2 or is this hopeless and I should get different cards?


Regarding Windows 2019

there seems to be a confusion between the 2x PSIDs you’ve presented.

In Mellanox website, under fw downloader for ConnectX-3 adapter:

MCX354A-FCBT is correlated to PSID MT_1090110019

MCX354A-QCBT is correlated to PSID MT_1090110018

I suggest the followings:

  • install in the Win2019 server Mellanox WinOF driver v5.50.5200. this will also install MFT (Mellanox fw tool) that will help you reveal the actual PSID that your adapter is being identified
  • Enter powershell (as administrator) and run: # mlx5cmd.exe -stat. There you can see the actual PSID.
  • Download now the fw v2.42.5000 as per the proper PSID
  • The other option is to “enable” the driver to install for you the latest HCA’s FW when running the “Installshield”

As for Esxi6.7u2

There is a VMware “Inbox Driver” v3.17.9.12 that supports ConnectX-3 on ESXi 6.7 platform along with the recommended fw v 2.40.5000, only the support to driver & fw issues will be handled by VMware and not mellanox

Try it to see if it works for you