EC2 crashes periodically

Set autoscaling for desirenmd number of one and set 2 as max, thus way the healthcheck will recognize unhealthy insurance and start a second instance while first one is going be destroyed,

https://docs.aws.amazon.com/elasticloadbalancing/latest/application/introduction.html

There are multiple options.

You can either scale vertically which implies getting a more powerful machine.

A better solution would be to scale horizontally. Look at setting up an auto-scaling group of EC2 machines with an Application Load Balancer in front to load balance traffic. You can look at this tutorial for guidance - https://docs.aws.amazon.com/autoscaling/ec2/userguide/tutorial-ec2-auto-scaling-load-balancer.html. For the content to be shared across multiple machines, you can look at EFS. Take a look at this video - https://pages.awscloud.com/Learn-to-Build-a-Cloud-Scale-Website-Powered-by-Amazon-EFS_0522-STG_OD.html

There could be many more options if re-architecture is an option.

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