TrueNAS Scale Setup Assistance-First Timer

Hey everyone and thank you in advance for any suggestions. I am newish to TrueNAS Scale. I have built a couple of small TrueNAS Core systems, but they were very simple. I want to build a more complex system and I was looking for some more insight. I have done a good bit of reading on the different vdevs and where they are applicable. I am always open to doing more if I am misunderstanding something. I am looking for feedback on what is a good/bad idea in this setup.

The setup is for a file server for a small business. There is some database usage, but majorly general file storage. When I upgrade the motherboard, I want to increase the ram and add 2 more 12TB drives to the backup vdev.
The backup vdev wouldn’t need a ton of throughput since it will be working during off hours.
But here we go.

I have:
1 x S1200btl
32 GB RAM (It’s maxed, I will be upgrading the board/RAM next year with a new budget hopefully)
8 x 12TB HDD’s (mix of 7200 RPM hdd’s)
2 x 3.84 TB SSD’s (v-nand ssd 883 DCT)
1 x 1TB nvme ssd ( MZ-VL21T0A Samsung PM9A1 1TB M.2 2280 Nvme Pcie GEN3 X4 SSD)
10GB ethernet port

I was thinking about purchasing:
1 x 320 GB nvme ssd
1 x 128 GB nvme ssd
2 x 500 GB nvme ssd’s

I was thinking I could setup:

File Server vdev:
1 320 GB ssd l2arc/slog
2 x 1 3.84TB SSD metadata
2 x 2 12TB HDD’s mirrored/striped data

Backup vdev:
2 x 2 12TB HDD’s mirrored/striped data

Jail/App vdev:
2 x 2 500GB nvme ssd’s

1 x 128GB Boot drive

Seems like you are using the term “vdev” when you actually mean pool.

Why use mirrors on your backup “vdev”?

When picking an SSD for SLOG use care needs to be taken as the requirements are quite unusual.

Take a look at this thread:

Also, you could use a fusion pool instead of your main pool and separate apps pool.


For L2ARC you want to have at least 64GB of RAM.
I believe you do not need a SLOG since you don’t seem to use sync writes.

A backup pool on the same system is kinda wasted, but that’s my opinion.

Suggested readings are Introduction to ZFS | TrueNAS Community, iX's ZFS Pool Layout White Paper and Some insights into SLOG/ZIL with ZFS on FreeNAS | TrueNAS Community.

1 Like

@Davvo Thank you for this. I wondered about the L2ARC because I always see suggestions that it’s only needed when the RAM is maxed. I have seen some mention the 64GB floor as well. Well, I am maxed and only at 32GB. So, I guess that means I don’t worry about the L2ARC until I upgrade the mobo, right?

@Stux Thank you for the insight. You are right, I was using vdev when I should have been using pool.

I have read some conflicting ideas about backups. I do want to be prepared for disk failure, but I do want to maximize storage. I guess the read/write speed doesn’t matter so much though. So, I could use the 4 disks in a Raid 5 setup.

I am going to read more about the fusion pools.

Yours is the edge case: if you really need the L2ARC you can add it.

A bit of advice: If this is for a business use, then NEVER EVER use the same machine for backup or for any type of redundancy.

Hardware can and will have a catastrophic failure at the least opportune moment and can take drives with it. I had a server do just that. A backplane hardware crash and burn took out all 4 drives in a backplane row killing one vdev in one pool and in turn the pool. Because it was a power issue it also took the server down. Now can’t power on to access the other pool. Fortunately this was easily recoverable by making some minor path re-configurations to use the backup server as the primary server while we bought and configured a new server and transferred files. No lost data and about 4 hours of lost time.

1 Like