Mixing stripe and mirror on same drives

[Passerby]

Hello everyone,

Repurposing and old PC with 8GB RAM (max for MB) and:
- 1x small spinning boot drive
- 2x large spinning data drives
- 1x SSD

I need to store on that machine important documents/photos (needs replication/mirroring), as well as some less important ones, that are easily recoverable and thus I really would prefer not to replicate these, but rather stripe them.

How can I achieve having floating capacity between mirrored datasets and striped ones?

I would use minio and create 2 buckets horizontally spanning the drives (1 with replication, and an another one without, think standard and IA storage class on S3), but it gets complicated accessing those files via SMB or adding any kind of Plex server or jails on top of it.

P.S.: would like to use the SSD as a cache drive for both datasets, to supplement the scarce RAM on that machine.

 

[jgreco]

8GB RAM is the bare minimum requirement to be able to run FreeNAS/TrueNAS for basic file service. This does not allow any room for "Plex servers", probably no jails except for the very tritest, and certainly no room for a "cache drive", which requires significant ARC space.

ZFS does not allow you to specify storage type on a per-dataset basis. It's per-pool. Your only choice here is to set up a mirror of the two "large spinning data drives". You can create a separate SSD scratch pool which is nonredundant if that's useful to you.