EC2 Instance upgrade or auto scale?

To allocate more memory and storage for your EC2 instance, you have a couple of options:

1. Instance Upgrade: You can manually upgrade your EC2 instance type to one with more memory and storage. This involves stopping the instance, changing the instance type, and then restarting it. However, this is not an automatic process.

2. Auto Scaling: EC2 Auto Scaling doesn't automatically increase the memory or storage of individual instances. Instead, it adds or removes instances based on defined conditions to maintain application availability and performance.

If you need to automatically adjust resources, you can use EC2 Auto Scaling to replace instances with new, larger instances. This can be done through:

1. Instance Refresh: This feature allows you to automatically update instances in your Auto Scaling group. You can trigger configuration updates such as changing to a new instance type with more memory and storage.

2. Launch Template Updates: You can update your launch template with a new instance type that has more resources, then use Instance Refresh to roll out these changes.

3. Scaling Policies: You can set up dynamic scaling policies that respond to metrics like CPU utilization. When triggered, these policies can launch new, larger instances and terminate smaller ones.

Remember, Auto Scaling is primarily designed to adjust the number of instances, not the resources of individual instances. If you need to frequently adjust individual instance resources, you might want to consider using a larger instance type or exploring other AWS services that offer more flexible resource allocation.
Sources
Amazon EC2 Auto Scaling now supports Instance Refresh within Auto Scaling Groups
Replace the instances in your Auto Scaling group - Amazon EC2 Auto Scaling
Increase or decrease compute capacity of your application with scaling - Amazon EC2 Auto Scaling

If you are looking to add more CPU or memory to an existing instance, you need to:
1/ Stop the instance
2/ Change the instance type to one with more or less CPU/memory
3/ Start the instance.

Autoscaling adds additional instances but to use it, you will need:
1/ A load balancer to distribute your traffic to more than one instance
2/ An application that can support more than one backend instance (and be fully configured on booting of additional instances)

Autoscaling is a great option but requires more planning than just enabling it.

For more storage, you can grow the size of the EBS volume that is used by your instance. See this doc for details: https://docs.aws.amazon.com/ebs/latest/userguide/ebs-modify-volume.html

Hope this helps!

Hi

To allocate more memory, change the EC2 instance type to a larger one. For more storage, modify the EBS volume size, then extend the file system. If you need auto-scaling, use an Auto Scaling Group (ASG) to add instances as needed. Make sure to stop the instance before changing its type, and extend partitions after modifying storage.