Data Loss Risk with c8gd.2xlarge EC2 Upgrade – Is it Safe to Stop or Downgrade?

Hello.

The local NVMe SSD (instance store) on c8gd.2xlarge instances is volatile storage.
This means that if you stop/start the instance, or terminate it, all data on the local SSD will be lost.
Therefore, any data you want to retain permanently should be stored on EBS.
https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/ssd-instance-store.html

Instance store volumes are suitable for temporary data that requires high-speed processing, as described in the following document.
Therefore, it is not suitable for storing persistent data.
https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/InstanceStorage.html

An instance store provides temporary block-level storage for your EC2 instance. This storage is provided by disks that are physically attached to the host computer. Instance store is ideal for temporary storage of information that changes frequently, such as buffers, caches, scratch data, and other temporary content. It can also be used to store temporary data that you replicate across a fleet of instances, such as a load-balanced pool of web servers.

Thank you for your response, It got me thinking, I'm running another EC2 instance of type m5d.xlarge and trying to understand its storage behavior. I need to know that my files under /var/www are safe if I restart the server.

Here's the output of lsblk:
NAME        MAJ:MIN RM   SIZE RO TYPE MOUNTPOINT
loop0         7:0    0  27.8M  1 loop /snap/amazon-ssm-agent/12051
loop1         7:1    0  27.2M  1 loop /snap/amazon-ssm-agent/11320
loop2         7:2    0  55.5M  1 loop /snap/core18/2887
loop3         7:3    0  55.5M  1 loop /snap/core18/2923
loop4         7:4    0  63.8M  1 loop /snap/core20/2599
loop5         7:5    0  91.9M  1 loop /snap/lxd/32662
loop6         7:6    0  73.9M  1 loop /snap/core22/2010
loop7         7:7    0  63.8M  1 loop /snap/core20/2582
loop8         7:8    0  49.3M  1 loop /snap/snapd/24792
loop9         7:9    0  50.9M  1 loop /snap/snapd/24718
loop10        7:10   0  91.9M  1 loop /snap/lxd/29619
loop11        7:11   0  73.9M  1 loop /snap/core22/2045
nvme0n1     259:0    0   300G  0 disk
└─nvme0n1p1 259:2    0   300G  0 part /
nvme1n1     259:1    0 139.7G  0 disk

ubuntu@ip-10-0-0-125:~$ df -h

Filesystem      Size  Used Avail Use% Mounted on
/dev/root       291G  225G   67G  78% /
devtmpfs        7.7G     0  7.7G   0% /dev
tmpfs           7.7G     0  7.7G   0% /dev/shm
tmpfs           1.6G  980K  1.6G   1% /run
tmpfs           5.0M     0  5.0M   0% /run/lock
tmpfs           7.7G     0  7.7G   0% /sys/fs/cgroup
/dev/loop0       28M   28M     0 100% /snap/amazon-ssm-agent/12051
/dev/loop3       56M   56M     0 100% /snap/core18/2923
/dev/loop1       28M   28M     0 100% /snap/amazon-ssm-agent/11320
/dev/loop2       56M   56M     0 100% /snap/core18/2887
/dev/loop4       64M   64M     0 100% /snap/core20/2599
/dev/loop5       92M   92M     0 100% /snap/lxd/32662
/dev/loop7       64M   64M     0 100% /snap/core20/2582
/dev/loop6       74M   74M     0 100% /snap/core22/2010
/dev/loop10      92M   92M     0 100% /snap/lxd/29619
/dev/loop11      74M   74M     0 100% /snap/core22/2045
/dev/loop8       50M   50M     0 100% /snap/snapd/24792
/dev/loop9       51M   51M     0 100% /snap/snapd/24718
tmpfs           1.6G     0  1.6G   0% /run/user/1000