LED behavior difference between BFB 2 and BFB 3 on BlueField-3 DPU

[t8741150]

When I was using BFB 2 with the BlueField-3 DPU, I could stop services such as opensmd, openibd, and bring down interfaces with ifconfig xxx down on the DPU’s Ubuntu system to keep the LED in the Link Up status.

However, after updating to BFB 3 (bf-bundle-3.1.0-76_25.07_ubuntu-22.04_prod), I can no longer reproduce the same LED Link Up behavior using the same method.

Is there any change or new configuration in BFB 3 that prevents us from controlling or maintaining the LED status manually as before?

[tuanama]

@t8741150

You can clarify about your procedure?, you need link up all the time even when the services is down?

[chenh1]

Hi @t8741150 ,

There is a firmware feature called Keep Link Up. When enabled, the physical link remains up even if the interface is brought down from the OS.
Please ensure that the mlxconfig KEEP_LINK_UP parameters are set to 1.

KEEP LINK UP options:

KEEP_ETH_LINK_UP_P1=<False|True>   When set, the NIC keeps the Ethernet link up as long as the server is not in standby mode.
KEEP_ETH_LINK_UP_P2=<False|True>

KEEP_IB_LINK_UP_P1=<False|True>    When set, the NIC keeps the InfiniBand link up as long as the server is not in standby mode.
KEEP_IB_LINK_UP_P2=<False|True>

For example, to check the current configuration:

mlxconfig -d xx:xx.x q | grep KEEP_ETH_LINK_UP_P1

If the value is set to 0, use the following command to enable it:

mlxconfig -d xx:xx.x set KEEP_ETH_LINK_UP_P1=1

After changing the configuration, please reset the firmware or reboot the system for the change to take effect.

Best regards,
Chen

[t8741150]

“Thank you for your advice — it was very helpful. The issue has been resolved.”