TrueNAS on Proxmox: Passtrough entire controller vs HDDs

[BigTonho]

Hello everyone, I'm setting up a server for the company where I work and I have a question about the "Passthrough" of the HDDs to a TrueNAS server hosted on Proxmox, but first I'll provide some information to try to generate some context:

The server basically consists of the following:

• Some Windows VMs to provide the sales system for about 10 PCs;
• TrueNAS Scale to store sales invoice files (in Brazil we need to store them for at least 5 years) and general work files;
• Some containers, mainly ADGuard and Photoprism/photosync to backup data from 4 smartphones that will store the files on the True NAS VM;

For this configuration, I set up the following:

• 1 SATA SSD to install Proxmox/store ISOs;
• 1 Nvme PCI-Express SSD to store the VMs;
• 3 x 4TB SATA NAS HDDs for the TrueNAS ZFS;

After reading some documentation and following some tutorials, I installed TrueNAS by exposing each HDD with its respective serial number in the VM configuration, in Proxmox. So far so good, the HDDs appeared in TrueNAS and I was able to configure RAIDZ1 without any problems!

But after researching some things I found this post on reddit:

https://www.reddit.com/r/selfhosted...nas_on_proxmox_vm_or_baremetal/?show=original

and this answer worried me:

BUT i'm afraid that passing through HDDs would be a problem in the future or if one of the HDDs failed i'd lose data, or even worse if the vm is somehow corrupted and can't restore backup that means i can't read the data, and it's all gone, that's my main concern.

"You should be passing through the controller, not the individual hard drives."

What does this mean? If one of the HDDs is degrading in the poll, will I not be able to replace it? Do I have to transfer the entire controller to it so that the functions can work "outside" Proxmox?

I ask this because, on the motherboard in question, the Proxmox M2 SATA SSD and the TrueNAS HDDs are on the same controller, and if I use the M2 SATA SSD, the first SATA port on the motherboard is disabled.

In this case, do I have to purchase another SATA controller before putting the server into production?

 

[louie1961]

I am not 100% sure of the answer for you. I am 99% sure that just passing through the drives is not going to be a problem if you lose one. Same for if the VM becomes corrupted, it shouldn't affect the data on the drive. BUT, that having been said, RAID is not a in any way a substitute for doing proper backups. The only way to truly protect yourself against data loss is a proper 3-2-1 backup strategy: Three data copies, two different types of backup media and at least one copy off site. I always backup my main NAS to a secondary NAS onsite and also use Rclone to send a copy of my files to Amazon Glacier in the cloud. There are certainly other tools you can use. I believe TrueNAS has a tool (cloud sync? ) that can do differential backups to Glacier (or other cloud platforms) so that you are not replicating your entire data set with each backup. The frequency at which you should back up is decided by your risk tolerance (i.e., set RTO and RPO objectives for your business and design to them).

 

[BigTonho]

I am not 100% sure of the answer for you. I am 99% sure that just passing through the drives is not going to be a problem if you lose one. Same for if the VM becomes corrupted, it shouldn't affect the data on the drive.

Ok, I'm more relaxed, I'll do a test HD exchange, since I ordered another identical spare HD, if something goes wrong I'll let you know!

BUT, that having been said, RAID is not a in any way a substitute for doing proper backups. The only way to truly protect yourself against data loss is a proper 3-2-1 backup strategy: Three data copies, two different types of backup media and at least one copy off site. I always backup my main NAS to a secondary NAS onsite and also use Rclone to send a copy of my files to Amazon Glacier in the cloud. There are certainly other tools you can use. I believe TrueNAS has a tool (cloud sync? ) that can do differential backups to Glacier (or other cloud platforms) so that you are not replicating your entire data set with each backup. The frequency at which you should back up is decided by your risk tolerance (i.e., set RTO and RPO objectives for your business and design to them).

Oh, of course, RAID is not a backup! Soon after I deploy the server I will set up another machine in another location to backup the VMs and most critical files from the NAS daily trought a VPN. Thanks for taking the time to answer me!