Workaround for Intel 'ixgbe' Supported Network Cards and Unsupported SFP/SFP+/QSFP Modules

Summary

This KB article addresses an uncommon issue related to Intel ‘ixgbe’ driver support in the kernels that ship with Swarm. Specifically, there may be rare occasions where the SFP/SFP+/QSFP modules that are used in the servers in question show up as being unsupported by the ‘ixgbe’ driver.

Workaround

The symptom of this can be seen in dmesg output for the node and would look similar to the following:

ixgbe: Intel(R) 10 Gigabit PCI Express Network Driver - version 5.1.0-k ixgbe 0000:02:00.0: failed to load because an unsupported SFP+ or QSFP module type was detected. ixgbe 0000:02:00.0: Reload the driver after installing a supported module.

What is being reported here by the ‘ixgbe’ driver is that the SFP/SFP+/QSFP module used with the NIC is unsupported by the driver’s whitelist. This can prevent the NIC from being brought online for use by Swarm and, as such, we want to eliminate this check to allow the NIC(s) in question to come on line. Fortunately, this can be done with a kernel command line argument for the driver as follows:

ixgbe.allow_unsupported_sfp=1

How this argument is applied to the Swarm kernel at boot will depend on the boot management platform being used (SCS, CSN, USB boot). We will cover the changes needed below for SCS for ease of reference. The steps are:

Log onto your SCS system as user ‘root’
At the command prompt, issue the following:

# scsctl network_boot config set kernel.extraArgs=ixgbe.allow_unsupported_sfp=1 -d  
# systemctl restart swarm-platform

Once step 2 is complete, you can now boot the affected Swarm servers to have it take effect, at which point the ‘ixgbe’ driver will be able to load and initialize the NICs using the unlisted SFP/SFP+/QSFP modules.