TrueNAS on HP Proliant Microserver gen 8

Howdy folks.
Started a topic a while ago here: What NAS option do I choose? - #7 by FredFerrell

However, I wanted to start afresh with some things more clear on my mind.
I’ve purchased a HP Proliant Microserver gen 8, it has 10 GB ECC RAM and runs a Xeon 4C/4T CPU.
I put a spare 120 GB SSD in the ODD for the OS.

Now, for the tasks at hand.

1 TrueNAS/ZFS needs to pass-trough the RAID controller or it will simply detect or ignore it?

2 I learned that the HDDs are not hot-swappable and the 1+2 HDD bay are SATA3 the rest SATA2.
Will it hinder my speed, as I intend to populate all 4 bays? Will buying a RAID controller is a better option?

3 After installing TrueNAS, will I be able to migrate the array, move to bigger drives or something similar?

Thanks in advance,

TrueNAS uses the ZFS file system which uses software RAID. You do not want to use a raid controller at all with ZFS.

What you can use is a HBA card which is essentially a method of just adding more SATA (or SAS) ports to your motherboard. An HBA card presents all the drives to the system and lets the software control them individually however it pleases.

Sometimes you can put an old-fashioned hardware RAID card into something called IT Mode which lets it act like an HBA, but I have never done this myself so I can’t speak to it much.

I recommend you watch some of Tom’s videos on the fundamentals behind ZFS / TrueNAS.

Another good resource that is quite specific to this topic is this video from Wendell

If you have a RAID controller and can’t put it in an HBA like mode, you can always create a virtual volume for each drive probably using JBOD or RAID 0. When the OS boots up it should see each virtual volume which will be mapped to an individual disk. I used to do this for VSAN deployments.

SATA2 is slower, but unless you have heavy workloads like database IO or VDI boots I doubt it will affect performance.

I would think you could decom a drive and just back fill it with a larger one, let it replicate data onto it and then do the next one until all are replaced. Another option is get a USB drive with a large enough disk for all the data and copy it over, then remove old drives and put in new ones. Once you rebuild your LUN/volume then you can copy your data back.

Hello and sorry for the long absence from the forums.
On my HP Microserver I installed Proxmox. The hypervisor was installed on a small 120 GB SSD, the real machine has 3 NAS300 HDDs connected to the machine RAID controller. While in Proxmox, I created a single ZFS RaidZ using those drives.
Now, for installing FreeNAS inside the hypervisor, I saw a few videos. However, as I understand it the steps will be the following:

  • Upload the FreeNAS ISO into the Proxmox.
  • Create a VM machine with a initial small hdd only for OS instal.
  • Create more volumes equal in size for creating an ZFS array.
  • Set up the shares and users

This is where is where confusion starts: Will FreeNAS see the volumes as they are and use the virtualized SATA controller? Do I need to specify something else?
Am I wrong somewhere?
Thank you beforehand for your time and answers,