Difference between i40e and i40en?

[Edouard Gaulué]

Hi community,

I just received a brand new server with an Intel X710 T4L inside. I 
hoped I could use it at 5GBaseT speed as claimed by Intel, but I couldn't.

In fact, I run ESXi 6.7U3 on this new server and it looks it doesn't 
support this speed (2.5G neither). I downloaded Intel driver source code 
and discovered there was an incompatibility between 5GBaseT and DCB. But 
then vmware support team, point me the driver used by ESXi is i40en and 
not i40e.

Are those drivers totally different? It looks to. Error strings found in 
vmkernel.log couldn't be found in the source code. Is there any way to 
get sources for i40en? For patching and rebuild.

Any idea on who I should write to discuss with those i40en driver 
maintainers? Here or totally out of scope?

Regards, Édouard