Can anyone refer me to or recommend introductory reading material that would cover the following questions:
What would be a typical disk layout? From what I‘ve seen so far, it could be
- 2 x SSD RAID-1 for the operating system
- 2 x SSD RAID-1 for a read-write cache
- The rest are HDDs, e.g. in a RAID-6 (RAID-Z2)
How large would you choose the SSDs?
Do the SSDs also get ZFS as file system?
At which level is disk encryption done? Are the system volume and the cache volume also encrypted?
How do I determine the memory requirement? There is a 32GB and a 128GB version of the TS-h1277XU-RP. Of course, the services on the virtualisation station need memory, but the unknown for me is the amount of memory needed for ZFS operations like deduplication, self healing, and snapshots.
What role does ECC RAM play? And is it only supported by the Intel version (TS-h1283XU-RP-E2236-128G)?
With the RAID-5 configuration in my previous NAS, RAID rebuilds after changing a drive always mean to hope that the remaining drives would survive the rebuild. So I would like to add another layer of redundancy with the new configuration: Would you go with RAID-6 (RAID-Z2), rely on cold-storage dumps, or do something else? How do I estimate the typical rebuild time of a ZFS RAID-5 (RAID-Z1) or RAID-6 (RAID-Z2) on these devices?
Is this a hardware RAID or a software RAID? How long do the RAID controllers last and can they just be swapped, keeping the existing data drives? Is the RAID controller monitored to detect possible problems? (I had this once in a server, where a RAID-controller problem showed up in the boot log and in a diagnostic tool and I ended up replacing the mainboard and the RAID controller while keeping the drives as they were.)
Is extending an existing RAID-6 (RAID-Z2) in size a problem? I was thinking of leaving some of the drive slots empty to add more drives over the next 5 years. But this QNAP intro video at 19:00 min sounds like one can’t just add another drive to an existing RAID. I think, RAID-Z expansion was planned to land in 2020. Is it there, yet? Can one trust it? What are the alternatives?
What flavor of ZFS are they using in QuTS? Do I need to buy a license to use ZFS?
How does the virtualization station perform? How does, for example, running postgres and redis databases on the virtualization station compare to running those within a docker environment on a separate server?