Instance reachability check failed after performing In-place upgrade from Windows Server 2012 r2 to 2019

Hello

Your instance type supports enhanced networking, therefore this attribute should be enabled.

You can run this commands on Cloud-shell on your AWS Dashboard , Ensure you are on the correct region where the instance is hosted.

Run the below AWS CLI command, insert the instance Id under the "instance_id" field.

aws ec2 describe-instances --instance-ids instance_id --query "Reservations[].Instances[].EnaSupport"

It Should give an output of "False"

Modify-instance-attribute by running the below AWS CLI command :

aws ec2 modify-instance-attribute --instance-id instance_id --ena-support

Run the first command AWS CLI command to describe the instances, The output should show as "True"

Reboot your instance, it should be back online

If the issue persists, suggest you restore your instance from your backup that you took before the upgrade. You can follow the step by step process from the start.

Resources

https://aws.amazon.com/ec2/instance-types/

https://docs.aws.amazon.com/AWSEC2/latest/WindowsGuide/enhanced-networking-ena.html

https://docs.aws.amazon.com/prescriptive-guidance/latest/backup-recovery/restore.html