Solving driver-related RDMA streaming issues with Ubuntu 22.04

This knowledge base article explains how to solve a driver-related RDMA streaming problem when using Arena SDK on Ubuntu 22.04.

Root cause

As of September 2024, there is an incompatibility between Broadcom NIC and the latest versions of Ubuntu 22.04 with a v6.x kernel. The Broadcom NIC driver only supports the 5.x kernel.

This article applies to you if you are doing the following:

• Using the Arena SDK with Ubuntu 22.04 with a v6.x kernel.
• Using a RDMA-compatible NICs manufactured by Broadcom. This includes all RDMA-compatible NICs supplied by LUCID.
• Attempting to stream using the RDMA protocol.

Workaround

The steps for this workaround are as follows.

1. To downgrade to the original general-availability kernel:

sudo apt-get update
sudo apt install --install-recommends linux-generic

1. Reboot the system, and obtain the grub menu.

• • On UEFI bios systems, press Esc during system bootup to get to the grub menu
  • On legacy bios systems, hold Shift during system bootup to get to the grub menu
  • Alternatively, update the grub config with the following steps:
    1. Open /etc/default/grub
    2. Comment out GRUB_TIMEOUT_STYLE=hidden if it exists
    3. Uncomment GRUB_TIMEOUT=0 and change the value to 5, or a higher
       number
    4. Save the changes
    5. In terminal, run sudo update-grub to apply the changes

This will give you 5 seconds (or the number of seconds entered for GRUB_TIMEOUT) to select an option in the grub menu before booting the OS.

3. Select Advanced options for Ubuntu, and make the selection to boot to the 5.15 kernel, and then complete the boot.
4. Run the Broadcom driver installer, which is included with the Arena SDK installation package.
5. If everything works as expected, you can remove the other kernels (using sudo apt-get purge) or configure grub to boot the 5.15 kernel by default.