That doesn’t really answer the question (big disks doesn’t necessarily mean they’re being utilized), but let’s assume it does. In that case, yes, you’d really need to use spinners, or a whole boatload of expensive SSDs. In short, then, the setup is going to be that have the SSD as your boot device, and your second volume mounted at /var/lib/nethserver. That volume would store all the data–email, file shares, web sites, etc. The OS goes on the SSD.
As to how to accomplish that, you have a few options:
- Using the installer, you can set up your partitioning scheme; partition/format the spinner there and tell it to mount at /var/lib/nethserver. This is probably the simplest way to accomplish this.
- Install as usual, then partition/format/RAID the spinners afterward at the CLI and mount them in the right place. Move any data that was already there onto the new volume.
- Install as usual, install OpenZFS on Linux, create a ZFS pool on the spinner(s), and mount that pool in the right place. Again, you’ll need to move a small amount of data over.
My preference would be the third option. It isn’t the simplest, but it gives you a ZFS pool for your data. That provides data integrity benefits (all data is checksummed, so corruption can be detected and fixed at the filesystem level), and also makes it trivially easy to expand the pool when it gets full.