[HL15] [Fully Built] Onboard Broadcom 3008 controller Passthrough


I have just purchased the HL15 as a full build version. And I was reading through the motherboard manual to understand all the specs.

I noticed with HL15 back plane, it connects 7 drives to the SATA onboard controller, the other 8 to the SAS onboard 3008 controller. And this onboard SAS controller is not sharing PCIe lanes with anything else.

So I’m thinking of this, would it be possible to install Proxmox and just pass through this SAS controller directly into a TrueNAS VM? As this controller is the only device on its own PCI bus, would this be possible?

I understand I will only be able to use 8 slots of the HDDs on the back plane, but I’m totally fine as I don’t need more than that. I think the benefit is to not buy a separate HBA card as we already have an onboard controller.

It might sounds like a weird use case, but I do want to make this more like an all-in-one solution.

I’m relatively new to this topic, excuse me if the question seems obvious.
Looking for suggestions from the community.

Thank you!

Yes. You might need to tweak a few things like the motherboard trying to boot from the disks connected to the HBA. See;


There’s a lot of tutorials and discussion about setting up TN VMs in Proxmox, so I don’t know if that config is or isn’t best practice. It would seem to limit your ability to create additional VMs or move them between hosts.

Thanks for the reply, yea I came across this post. I haven’t received my server yet, so I was thinking of posting it here, to see if anyone else has already tried it out.

It would seem to limit your ability to create additional VMs or move them between hosts.

When you mention limit ability to create additional VMs or move between hosts, are you referring to Proxmox HA Cluster?

I think with this setup, I’ll have to make sure this TrueNAS VM only and always runs on HL15 server. Regarding other VMs, I’m thinking of utilizing the 1 TB NVMe on the motherboard as Proxmox boot drive + VM store. (I will back up for sure)

And maybe letting other VMs (lightweight RKE2 node) free to move across my cluster with Ceph storage.

I guess another good option is to just run truenas scale barebone and create a linux VM run the RKE2 node. lol But i just really want the Proxmox cluster and easy to manage everything in one place lol…

It really depends on your use case(s), either known or leaving flexibility for lab experimentation. All I meant was what you pointed out, that all 8 disks for the SAS controller will be dedicated to the TrueNAS VM, You won’t have as easy a time re-allocating one of those disks or disk bays to some other project or VM as if you passed the disks to TrueNAS. That might not be a problem if all the other VMs or containers you want to run aren’t space heavy. You do have the other 7 SATA drives outside TN. It might be a problem (?) if you want to set up the Proxmox box to be a pretend Ceph cluster.

The downside of TN as the bare metal OS is that it’s VM and container support isn’t very robust. You’d run TN as the host OS if your main focus was simple management of ZFS storage with only one or two VMs or some prepackaged container apps running. You’d run Proxmox as the host if your main focus was VM and container flexibility and less on a pretty UI for a ZFS pool.

You shouldn’t rule out the Houston/Cockpit environment that comes preinstalled on the full build.

Thanks for the reply. Yea i think I’d try with Proxmox and passthru first. And see how things going from there.

I’m still waiting for my order to arrive, I’m on us west. It’s taking forever to receive my order, lol.

I’m in WA state. The process didn’t seem very coordinated (I got the “your order has shipped” email the same day Fedex delivered it), but I think once the package has crossed the border to their distributor in NY, it should be overnighted or next-business-day’d to the lower 48 states.