Truenas and HBA Problem

TrueNAS General
1

Hey folks, need some advice from the seasoned sysadmins here.

We recently had to move our entire SMB virtualization setup (about 30 VMs) from Hyper-V to oVirt. The budget only allowed for three new servers with these specs:

  • Two powered servers with Intel Silver.

  • One weaker server with Intel Bronze and 32GB RAM.

  • The disk space is about the same on each (128TB).

Nothing fancy, but the ideal setup seemed obvious: use the two powerful servers as oVirt hosts, and the weaker Intel Bronze machine as a TrueNAS Core/Scale storage box.

But here’s the kicker we discovered during the hardware prep: the RAID controllers. All servers have a 9640-16i as the RAID controller, which can’t do HBA mode. But one of the two powerful servers even has two – an additional 9300-8i, which can do HBA.

You’d think, “Just move that HBA card to the server destined for TrueNAS.” But since that 9300-8i version only has 2 ports, 4 out of the 12 drive bays on that server would just go unused.

So I’m stuck and would love your input. What would you do?

  • Come up with a different storage setup? (I figure Ceph/Gluster are out of the picture because of the weak server – it would just bottleneck everything).

  • Or try to hunt down a 9300-16i version?

    I’m open to any ideas! How would you design this oVirt setup with the hardware we have? I want to make it as reliable as possible, given the budget and config constraints.

2

i see three possible configurations for connecting 12 SATA/SAS drives:

  • two 9300-8i HBAs
    Provides the highest aggregate host bandwidth across two PCIe ×8 links and reduces contention per drive. Also improves resiliency, since each HBA only controls part of the drives.

  • one 9300-16i HBA
    All drives share a single PCIe ×8 link. Simpler setup, fewer components, and sufficient for workloads where per-drive throughput is not critical.

  • one 9300-8i combined with a SAS expander
    Increases the available port count while keeping the same single PCIe ×8 host link. Effective for many-disk HDD setups where sequential throughput per drive is not a limiting factor.

The optimal choice depends heavily on your motherboard’s available PCIe slots/lanes and on the intended drive type (HDDs vs. SSDs) and workload characteristics.

3

Thank you for answer! Great news. I managed to track down another 9300-8i, so now we can use TrueNAS.

But that brings up a new question: how do you handle data protection for storage that’s a single instance, where you can’t mirror or sync it to identical hardware?

Specifically for TrueNAS SCALE:

  • Is there a built-in way to back up the entire storage pool to a specified location?

  • And how complex is the Disaster Recovery process if we ever need to restore from that backup?