How to load the ena driver on Amazon AWS?

Question

I'm trying to load the ena driver on a Ubuntu VM.

According to the documentation, my VM has the vif low-performance driver:

ubuntu@ip-172-31-14-190:~$ ethtool -i eth0
driver: vif
version: 
firmware-version: 
expansion-rom-version: 
bus-info: vif-0
supports-statistics: yes
supports-test: no
supports-eeprom-access: no
supports-register-dump: no
supports-priv-flags: no

However, I have already compiled and loaded the ena driver as explained in the AWS docs and in the driver docs:

ubuntu@ip-172-31-14-190:~$ lsmod | grep ena
ena                    86016  

Am I missing any steps here?

Answer 1

If either aws ec2 describe-instances --instance-ids instance_id --query "Reservations[].Instances[].EnaSupport" or aws ec2 describe-images --image-id ami_id --query "Images[].EnaSupport" (where instance_id is your (i-e04566365f208b6584) instance id and ami_id is your AMI's ID (ami-6365f208)) doesn't return "True" something is not marked as supporting ENA.

If it's your instance. Stop it, and run aws ec2 modify-instance-attribute --instance-id instance_id --ena-support to enable support and restart it. If it's your AMI, you'll either have to select an AMI that already has ENA support, or make your own from an instance that's been tagged (per above) as supporting ENA.

If your AMI already supported ENA, after running the above command, start it back up and ethtool -i eth0 should show support. If your AMI was the problem, you'll need to launch a fresh instance from an AMI that has ENA support.

https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/enhanced-networking-ena.html#enhanced-networking-ena-linux

Note that even though it says the AMI is optional, I've found that not to be the case. An AMI with support was required for me.