Is this config sensible?

[arcadeperfect]

Hi

I have novice questions...

Use case: NAS with 1 fast pool for serving near uncompressed video (exr sequences) for VFX work, and 1 large capacity pool for backups. Needs to be physically compact. Possibly in a custom enclosure. Also might run the occasional VM and host an Emby server from the big pool.

Exr sequences are huge but generally the same small chunk will be accessed a lot as that section is worked on, so I think caching will work well for that?

So I'm thinking:

• Mobo / CPU - As yet undecided mini itx Xeon based server mobo with 10g ethernet built in, minimum 64 gigs ram
• Fast pool - 8 sata SSD's connected to a pcie HBA, mounted in the icy dock SAS backplane or something similar, striped for max performance (maybe some parity? will this reduce write performance much?)
• Big pool - 5 spinning disks mounted in one of the various 3 x 5.25" hot swap bays connected to the mobo's sata ports, configured with parity for max integrity 5 disks can provide. Write speed is not important. Is SLOG worth it? Because I'm low on ports...
• 6th sata port for boot volume (or SLOG and boot from USB)

Is there any point in an NVME l2arc in that config? Not sure it would be any faster than the striped sata ssd's. Or I could go for more redundancy in the ssd's and add the cache?

The data would all be accessed from the fast pool, but that would be regularly backed up with snapshots to the large one (does this make sense?).
Large pool would in turn be backed up to backblaze but much less often.

Thanks for any advice!
A

 

[ChrisRJ]

Needs to be physically compact.

What does that mean? People have vastly different ideas about what "compact" means for them.

What are the capacity and IOPS requirement are we talking about?