Install to SSD System Drive with RAID1 spinning rust for VM's and Containers

[Chris Thompson]

I have a i7 based machine with 32GB of RAM, a 250GB SSD, and two 4tb spinning rust drives. Planning to turn this into a Proxmox host and want to understand where in the install process could I create a ZFS RAID1 pool using the two spinning rust drives for the purposes of hosting the VM and Container storage? I'd use the SSD as the Proxmox system drive.

Should I install Proxmox first and then create the ZFS Raid1 pool? Or should I do this as part of the install routine?

Thanks in advance. Appreciate the feedback

 

[Dunuin]

You can create a ZFS mirror with those 2 HDDs later after installing.

And by the way...proxmox only uses some GBs so 220+ GB are usable on your proxmox drive to store VMs. HDDs are crappy at running VMs so you might want to run the VMs of that SSD too and use that HDD mirror for you other data.

 

[Chris Thompson]

You can create a ZFS mirror with those 2 HDDs later after installing.

And by the way...proxmox only uses some GBs so 220+ GB are usable on your proxmox drive to store VMs. HDDs are crappy at running VMs so you might want to run the VMs of that SSD too and use that HDD mirror for you other data.

Thanks for the reply. This is mostly for a basic home lab for educational purposes. I realize spinning rust isn't ideal for VM's. That brings up another question, and perhaps I should pose this elsewhere. But does Proxmox support the concept of SSD caching in any of the storage mechanisms? Just a curiosity...

 

[Dunuin]

ZFS can use SSD caching but in most cases it is useless:
Read cache = L2ARC = only usefull if you already maxed out your RAM. If you can add more RAM, buy more RAM instead.
Write cache = ZIL/SLOG = only used for sync writes. Normally nearly all writes will be async and the SLOG isn't used at all.

If you really need the speed/iops use (enterprise grade) SSDs instead of HDDs. Today HDDs are only useful if you need big but slow cold storage. SSD caching won't make that much better.