How can the system admin ensure that the instance does not get terminated?
Update the Auto Scaling group to ignore the instance reboot event
It is not possible to change the status once it is marked for replacement
Manually add that instance to the Auto Scaling group after reboot to avoid replacement
Change the health of the instance to healthy using the Auto Scaling commands
Explanations:
There is no option to configure Auto Scaling to “ignore” an instance reboot event. The health check relies on instance status, so this would not prevent termination.
It is possible to change the instance’s health status. The instance is not permanently marked for replacement unless it remains unhealthy.
Adding the instance back manually will not prevent the termination. Auto Scaling will still replace it if it is marked as unhealthy.
By using the Auto Scaling commands to change the health status of the instance to “healthy,” the system will prevent termination and replacement.
In my opinion, the answer is:
Change the health of the instance to healthy using the Auto Scaling commands