I was reading your article and just want to add that this is a well known behavior and is not only related to EC2 I3 instances. This type of storage is called instance store volume and by its nature is ephemeral. It has nothing to do with the fact that NVMe is nov-volatile and therefore permanent storage. The deeper reason why your data is lost when stopping and starting an EC2 instance is that your EC2 instance will be hosted somewhere else most likely on a different host insfide AWS and therefore your EC2 instance will get a fresh newly provisioned instance store volume. Instance store volume can be considered like a directly attached storage (DAS) while Elastic Block Storage (EBS) is more like a network attached storage (NAS). If you restart EC2 you will keep the same instance store volume as well as your IP address. But if you stop/start EC2 you will lose access to your instance store volume as it is ephemeral as well as be assigned a new ip address. For that reason only store data inside the instance store volume if you can afford to lose it or have an easy way to recover or reproduce the data from somewhere else. I hope with this additional knowledge it makes now perfect sense and doesn't look so strange any more.