Ensuring Ethereum chain data is stored on my SSD drive

I’m using a cloud server. I followed the guide to set it up and now am arriving at the Starting Rocketpool section, but nowhere did I tell RocketPool where my SSD mount folder is. And I know with a full node, I need it to use a lot of space.

So I decided to do it myself with:

$ sudo mkdir /ethereum
$ sudo fdisk -l | grep 2T # find the 2T SSD drive
/dev/sda3  4194304 4194301951 4190107648   2T Linux filesystem
$ sudo mount /dev/sda3 /ethereum

But then to my surprise, I checked the /ethereum folder, and I see that it’s already being used with 21G of files?

$ df -h /ethereum
Filesystem      Size  Used Avail Use% Mounted on
/dev/sda3       2.0T   21G  1.9T   2% /ethereum
xxxxx@xxxxx:~$ sudo fdisk -l
Disk /dev/sda: 1.98 TiB, 2147483648xxx bytes, 4194304xxx sectors
Disk model: xxxxxxxx  
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: gpt
Disk identifier: xxxxxxxx

Device       Start        End    Sectors Size Type
/dev/sda1     2048       4095       2048   1M BIOS boot
/dev/sda2     4096    4194303    4190208   2G Linux filesystem
/dev/sda3  4194304 4194301951 4190107648   2T Linux filesystem

$ ls /ethereum | head -n 10

Did rocketpool automatically already find the 2TB SSD drive without me needing to mount it, and when I created a new folder this is just an alias?

Is this the correct setup? I’m a little skeptical.

Are you using the Docker (default), hybrid or native mode?

By default smartnode uses Docker containers and volumes and the data is in /var/lib/docker/volumes/

Docker! and hm, I see. OK checking that folder, it is currently empty.

I made the mount disk just be the root /, like so:

$ lsblk
sda      8:0    0   2T  0 disk 
├─sda1   8:1    0   1M  0 part 
├─sda2   8:2    0   2G  0 part /boot
└─sda3   8:3    0   2T  0 part /

And thus, I went ahead and changed /etc/docker/daemon.json to:

    "data-root": "/docker"

This seems correct, but how can I test that everything is working OK with this disk setup?

(Unless you think I should change that JSON file to use /var/lib/docker/ instead?)