Conflicting information regarding R730 ZFS Options

[jmm889901]

TLDR: What are my ZFS/hardware raid options for a 16-drive R730 with a Dell H730p mini (embedded)? I am not concerned about the storage/RAM efficiency, as we have an excess of both.

Hey all, I have somehow ended up volunteering to configure Proxmox on a donated R730 for a local charity shop that focuses on refurbishing donated laptops and desktops. The current machine they use is struggling to keep up with even the current load, and so they want to move over to something more capable as they take on more people.

Use case:
The current machine runs bare-metal Windows Server with some account stuff, but was mostly created for file sharing and (primarily) PXE boot for installing custom images onto freshly wiped machines.
The goal with the new machine is to separate the file server and PXE stuff from the Windows server, if possible, as well as to facilitate some basic web hosting for a local Wiki.
The main current issue I am confused about is how to configure a RAID. Part of the reason for the move is that they have already suffered some data loss due to one of the two drives in the old server dying (thankfully, not the OS drive; it was mostly ISO images that were lost), and so backup and RAID are a concern.
New machine:
The r730 in question has a h730p mini with (I think?) the latest firmware (7.5.5.9) and 16 1.2tb SAS hard drives, and 128gb of ram
This is quite a lot more storage than we need, but it does give us (by which I mean me) wiggle room to try different drive configurations.

I have seen a lot of conflicting information regarding whether or not ZFS/software raid in general plays nice with these controllers (even on HBA mode), and ideally, we would rather avoid spending money on new/replacement components (such as a different controller)
Proxmox itself is installed on an internal SSD, though I would like to get a second (I'm sure we have one lying around) and reinstall Proxmox with a ZFS mirror, since that is not connected to the RAID controller.

My main questions are:
Given that this is a hardware raid controller, am I better off just doing hardware raid or switching to HBA mode and using ZFS
Does
How does HBA mode on a given drive (according to iDRAC) differ from HBA mode for the entire RAID controller?
Does ZFS *actually* work on this controller in HBA mode? It does report the drive names and smart scores correctly in Proxmox (at least, they match with what the iDRAC hardware screen says)
If I am using ZFS, but have a VM backup drive that is not, is this a reasonable way of being relatively safe from ZFS configuration shenanigans

I have been researching this for a few hours, but I've heard everything from "No absolutely never do this" to "It's fine" to "It's fine for a while, then breaks at 50% usage", so I am not really confident making that call, given that I won't be available 24/7 to fix issues that pop up.
I am not overly concerned about the approaches to RAM or storage usage, as this is coming from a machine with 32 GB of RAM and 3 TB of storage, so we have plenty to work with. The current plan is to mirror most things.

Thanks for reading my rambling. I appreciate any advice you can give. I don't have a lot of experience with this, it just happened that I was the only one available with *any* experience.

PS 1: Does Proxmox have any inbuilt file sharing stuff, or would it be best to use a container hosting it?
PS 2: I am correct that SATA drives can go on SAS connectors yes? It likely won't be an issue for a while, but while we don't get a lot of SAS drives donated, we do get a lot of SATA drives (though I suppose using second-hand drives to replace dead drives isn't a fantastic idea).

 

[LnxBil]

Does it have to be ZFS? If not, just use ext4 (directory storage) or LVM(|-thin).

I have seen a lot of conflicting information regarding whether or not ZFS/software raid in general plays nice with these controllers (even on HBA mode)

The official recommendation, which is the only information that counts, is to NOT use a RAID controller. Even in HBA-mode, the disk may not be passthroughed entirely and can interfere with how ZFS works.

Does ZFS *actually* work on this controller in HBA mode?

technically yes, but in an unwanted configuration. You can live with it, but it's not the optimal use case for ZFS.

If I am using ZFS, but have a VM backup drive that is not, is this a reasonable way of being relatively safe from ZFS configuration shenanigans

Having different disks for data and backup is always good. I don't get what ZFS configuration shenanigans you mean. You setup your ZFS in the beginning and then just use it without ever touching it. If you do everything via the GUI, you will not even have to use the zpool or zfs commands.

I have been researching this for a few hours, but I've heard everything from "No absolutely never do this" to "It's fine" to "It's fine for a while, then breaks at 50% usage", so I am not really confident making that call, given that I won't be available 24/7 to fix issues that pop up.

Then don't use a system in which you can control everything. ZFS on HBA (not HBA-mode) works and is the recommended way to go. If you use it on RAID controllers, you could have a unhealable raid punch hole and have data loss, or any other strange effects.

Does Proxmox have any inbuilt file sharing stuff, [...]

It's a hypervisor, so no.

I am correct that SATA drives can go on SAS connectors yes?

Yes, but not vice versa. SAS drives have better and more consistent I/O response times, so replacing SAS with SATA does often yield in slower pools. You can use them, yet I would invest the time to figure such problems out in advance (e.g. with iostat -x and look at the await columns).