Migrating from Freenas to virtualized freenas within proxmox - tips?

[SillyPosition]

Hi all,
I have a server that is running freenas with few encrypted drives, and two flash disks that acts as a mirrored boot drive.

I would like to migrate to proxmox, and have the entire setup I already have today, running within a freenas VM.
That means passthrough the hba controller.

Any tips on the correct way to handle this procedure? Something specific I should do?
Im very new to proxmox ve, if I virtualize it in virtualbox would I gain any good insight to how to do the actual migration?
When installing the OS, where do I install it to, given that I have a single controller and I plan to pass it to the VM in order to be able to immediately import my entire setup and have it working with hopefully low level of effort?

 

[Dominic]

Im very new to proxmox ve, if I virtualize it in virtualbox would I gain any good insight to how to do the actual migration?

Yes, I think so. You can run Proxmox VE as VM in VirtualBox. Add some disks to the Proxmox VE VM and then you can try the disk passthrough to a VM that is created in Proxmox VE (nested virtualization).

 

[hy0ug0]

Hi @SillyPosition , did you successfully achieved your migration ? I planned to do the exact same things migration my TrueNAS server to a virtualised environnement inside of Proxmox so if you have any advice I'm listening !

 

[SillyPosition]

Hi @hy0ug0 , unfortunately I haven't got the time to do it yet.
I'm still unsure about how it would work with only my builtin storage controller, I'm not sure how it would work and I'm more inclined to try and figure out how to manage nfs/smb/zfs storage kinds directly from proxmox, as once I have a way to manage my data I dont really need freenas.
I already have my entire stack of services run in docker vm, so I wouldn't care much further if I have proxmox.
What board do you have and how are you planning to passthrough the disks?

 

[hy0ug0]

I've this card LSI 6Gbps SAS HBA Fujitsu D2607-A21 which is managing 8 of my 10 disks, the last 2 are directly connected to my motherboard which gonna be a problem. The TrueNAS OS is installed on 2 USB dongle.

 

[SillyPosition]

@hy0ug0 Isnt it a GOOD situation? You have a spare pci sata controller that you can dedicate to the freenas vm.
This is what Im missing.
So why its a problem?

 

[hy0ug0]

The problem is that only 8 disks are connected to the controller so I would have to buy another one for the extra 2 disks that are connected to the motherboard...

 

[SillyPosition]

Ah, ok
I *think* that if you have onboard nvme you can use this as the installation for proxmox, and then passthrough the builtin controller.
This is what I was hoping to try.
I think that the USBs are considered seperate controller as well, but again I couldnt yet try.

Do you think that its enough to simply take out the Freenas USB's that has the OS, and simply install proxmox to another USB drive and be able to revert back if things dont work well?

I think that Truenas 12.0, since it already uses openzfs, that the pool can be imported to both OSs without issues, and lay down a good testing environment...what do you think?

 

[Dunuin]

Don't install Proxmox to a USB-Stick. It is write heavy and will destroy it really quick. For Proxmox use 2 mirrored SSDs using SAS/SATA/PCIe connected to you mainboard or a HBA you don't passthrough.

 

[hy0ug0]

@SillyPosition Regarding the import of my existing pools, if I passthrough the HBA it will be transparent for Proxmox so my guess is that I should not have any issue with that ? At least I hope because I don't want to loose all my data that are on the pools...

Otherwise my plan would be the following:
- buying an other HBA controller this way all my disks dedicated to TrueNAS can be passthrough (the 10 of them)
- buying an NVMe for the Proxmox OS install (which size is recommended ?)
- adding 2 SATA SSD in mirror for the VMs data that I will connect to my motherboard controller directly (if new to Proxmox but if I understand it's a good practice to have VMs intall/data on a separate disks than the Proxmox OS install itself ?)
- finally I will export my current TrueNAS configuration and reinstall it inside a VM and then import my existing pools

 

[Dunuin]

@SillyPosition Regarding the import of my existing pools, if I passthrough the HBA it will be transparent for Proxmox so my guess is that I should not have any issue with that ? At least I hope because I don't want to loose all my data that are on the pools...

Otherwise my plan would be the following:
- buying an other HBA controller this way all my disks dedicated to TrueNAS can be passthrough (the 10 of them)
- buying an NVMe for the Proxmox OS install (which size is recommended ?)
- adding 2 SATA SSD in mirror for the VMs data that I will connect to my motherboard controller directly (if new to Proxmox but if I understand it's a good practice to have VMs intall/data on a separate disks than the Proxmox OS install itself ?)
- finally I will export my current TrueNAS configuration and reinstall it inside a VM and then import my existing pools

Its not really a problem to just use 2 mirrored SATA SSDs for Proxmox and VMs. That way your boot disk is atleast mirrored too. If you just use one NVMe SSD as boot drive and it fails you need to order a new one and need to install and setup Proxmox again. That might take a week where you can't access your FreeNAS data. Better get two reliable SATA SSDs with powerloss protection than 3 cheap consumer ssds.

 

[hy0ug0]

Ok and what size of SSDs would you recommend ? For let's say Proxmox OS, TrueNAS VM and 2-3 other VMs ?

 

[Dunuin]

That really depends on the 2-3 other VMs and if you want to use snapshots or if you use HW Raid. If you don't want to installl proxmox ontop of a Debian but you want software raid you only can use ZFS if you want to mirror. For ZFS 20% of the disks should be kept free and you will loose some space because of padding. 2x 100GB should be fine for Proxmox + TrueNAS alone with 20% kept free for ZFS and enough space for snapshots.

 

[hy0ug0]

I was thinking at 2 X 1TB SSD, it should let me 750GB of available space

 

[Dunuin]

But remember that that it isn't recommended to use consumer/prosumer grade SSD for ZFS. Might be a better idea to get smaller enterprise SSDs but with better durability, long term performance and powerloss protection instead of a big cheap consumer SSD.

I for example got a write amplification of around factor 20. 30GB of real data need to be stored per day but it is written 600GB per day to the SSD. That might kill cheap SSDs quite fast. Especially if you got alot of sync writes and your SSD doesn't support powerloss protection and therefore can't use caching what will highly increase the write amplification. Using SSDs with SLC/MLC flash and powerloss protection greatly lower the write amplification.

 

[hy0ug0]

@SillyPosition I did manage to do it successfully so don't hesitate !