Another OS/VM Partition Question for a new machine

[Carl J]

A few days ago I posted a question regarding my hard drives layout for Proxmox, and now that's pretty much gone out the window. I'm picking up an older server today, so again, will be installing Proxmox (I think I've spend more time installing/setting up machines, than actually letting them do their thing)

So the question is, what are the Pros/Cons of having a dedicated OS drive and another dedicated VM drive? Does it matter?

I can either go with:
- OS: 2 x SSD Hardware (RAID 1)
- VMs: 2 x SAS HDD (ZFS RAID 1)
- Backup: Some HDD

Or:
- OS + VMs: 2 x SAS (ZFS RAID 1)
- Backup: Some HDD

In either case, I would have a dedicated backup drive for the VMs, and have another machine that will also be doing the backups. So hopefully if I have to restore I won't have to copy over the network.

Is there a penalty for having the VMs on a separate drive than the host? I would imagine if there was, it wouldn't be minimal (not like I'm going to run some mission critical VMs on the machine).

Only advantage I can see is that if the OS or the VM drive goes down, there would be slightly less time setting it back up as I would only have to rebuild one of the drives.
Disadvantage of having of having two, would be some wasted space on the OS (OS is small, and there's only so many ISOs that I would need to download)

Can the Proxmox server back up the entire machine, and not just the VMs?

Thanks again

 

[Dominic]

Is there a penalty for having the VMs on a separate drive than the host?

Not really.

Having the OS separate also makes wiping and creating a fresh installation easier.

Can the Proxmox server back up the entire machine, and not just the VMs?

You can create backups of your guests and manually copy folders like /etc/pve in addition. Making this easier is on the roadmap of PBS.