[Advice Needed] Best setup for 2x HDDs + 2x SSDs: ZFS or mdadm + LVM?

[wigg3]

Good day,

I've got a server with 2x2TB HDDs and 2x512GB SSDs. I want to mirror the HDDs into 1 array, and the SSDs into another, and give all my VMs have access to both arrays, so the boot disk lives in the SSD array and the HDD array is used for backups. I only got 32GB of RAM. What's the best setup for this kind of hardware?

I've never used ZFS before so I don't know how to handle disk failures, hot swaps, and these sorts of things in ZFS. How hard is it, what kind of RAID/array setup should I use, and does it make sense to use ZFS for this kind of setup?

Thanks

 

[LnxBil]

Depends on your support status. If you want to buy a subscription and want help from Proxmox staff, you have to use ZFS, mdadm is not supported.

If you want to do everything manually, you can do mdadm. You need to use thin-LVM if you also want the capability to snapshot, or just use files, e.g. qcow2 and you will have snapshots as well.

In general, I'd also look into bbcache/flashcache LVM, so that you will only have 2 TB of storage, but SSD accelerated so that often used files are extremely fast to access. In this setup you would have to md raids and combine them to one cached block device on which you install and use LVM.