Hi,
We have been having the same problem since last October when we upgraded to esxi 6.5 and in turn started using the i40en nic driver. With this driver on every few weeks one of our hosts locks up. This post nails the problem better than I can describe Install ESXi 6.5 on R730 with Intel X710 |VMware Communities
Our workaround was to downgrade to the i40e version, unfortunately doing this makes VMware non compliant in update manager and because us IT guys have serious OCD its very annoying. It's also not good as we like to keep a visual view of these hosts so we know when to patch them.
Is this issue going to be fixed? Just to note on more than one occasion we have had production hosts go down because of this issue and we have had to explain to our staff.
Regards