With TrueNAS yes, a sata card connected to a bare drive is the preferred way. I have done it differently with enterprise hardware and virtualization but it’s not really supposed to be done that way. And ZFS is not technically “RAID” in the classic sense, but it does implement its own RAID‑like redundancy (RAIDZ and mirrors) as part of an integrated filesystem and volume manager. There are also things you can do with faster NVME drives like SLOG, L2ARC, and SPECIAL vdevs to store pool metadata. But some of these can fail and wipe out all your data if you aren’t careful. So read a lot.
Second hand drives are fine in my opinion as long as SMART is not reporting any immediate errors. Just assume you will have failures and have spares built into the zfs volume.
I’m not an expert by any stretch but I have been doing this for 10 plus years so I have some experience.
With TrueNAS yes, a sata card connected to a bare drive is the preferred way. I have done it differently with enterprise hardware and virtualization but it’s not really supposed to be done that way. And ZFS is not technically “RAID” in the classic sense, but it does implement its own RAID‑like redundancy (RAIDZ and mirrors) as part of an integrated filesystem and volume manager. There are also things you can do with faster NVME drives like SLOG, L2ARC, and SPECIAL vdevs to store pool metadata. But some of these can fail and wipe out all your data if you aren’t careful. So read a lot.
Second hand drives are fine in my opinion as long as SMART is not reporting any immediate errors. Just assume you will have failures and have spares built into the zfs volume.
I’m not an expert by any stretch but I have been doing this for 10 plus years so I have some experience.