Hi, I’m new to TrueNAS but am looking at getting everything setup soon with either TrueNAS or HexOS which I understand uses TrueNAS. I have a mixture of hard drives although they’re only two different sizes, several 20tb and several 24tb drives. I wonder what that be ok, or do you think it complica…

How many drives of each do you have in total? Any particular use case? Whats the rest of your build look like & how are you planning to connect the drives? Nothing wrong with having two separate pools; one for 20tb and one for 24tb drives. Nor do I think it could complicate things much at all - may…

Thanks, I have 8 x 20tb drives and 4 x 24tb drives. They’re for a home server (Plex) and I’m planning on connecting them via the motherboard plus a 10Gtek 6-Port PCIe Expansion Card, PCIe x4 to 6X SATA 3.0 (6Gbps) Controller. That’s great to hear it won’t be an issue :slight_smile:

Have you verified those controllers and expansion card are recommendations? [image] Multiply your problems with SATA Port Multipliers and cheap SATA controllers Resources This resource was originally created by user: jgreco on the TrueNAS Community Forums Archive. Please …

You can also create a pool of mirrored vdevs. Each mirror consists of either 20tb or 24tb drives: graph TB pool[(ZFS Pool)] --> mirror0[mirror-0] pool --> mirror1[mirror-1] pool -.-> dots[...] pool --> mirrorX[mirror-X] mirror0 --> sda[20TB]@{ shape: lin-cyl} mirror0 --> sd…

[image] LostBoyNZ: I have 8 x 20tb drives and 4 x 24tb drives. They’re for a home server (Plex) Ok, mirrors for Plex could be suboptimal. Perhaps, 3x 4-wide raidz1 vdevs would be better in terms of space efficiency. Or some fancy raidz2 geometry.

Apologies, I listed the wrong part there, I do have an LSI SAS 9300 16I HBA Card, which seems to be one of the recommendations yes. I’ll be using them with Mini SAS to SATA adapter cables, which I hope will be ok! The 10Gtek 6-Port was something I purchased before I asked about recommendations late…

8 20TB in a Raid-Z2 VDEV and 4 24TB in a Raid-Z2 VDEV. That gives you two different pools. If you have easy to restore data, you could go down to Raid-Z1 for more space with the 24TB drives.

[image] LostBoyNZ: It seems there’s a few possible ways to do the setup in terms of drive pools? Yes. You should read this guide . Iirc, it is recommended that vdevs within the same pool would have the same redundancy. That’s why if you go with raidz2 for 20tb drives, you should do the same f…

On second thought, you don’t have many 24tb drives – the loss of 4tb on each will result in “only” losing 16tb. That is less than one extra 20tb parity drive. Let’s make some calculations. You have 24x4 + 20x8 = 256TB of raw space. If you go with mirrors, you will get 128TB of usable space. If yo…

I’d also consider tossing an ssd (or two for a mirror) for apps & vms. I don’t think you’d lose too much if you tossed the 24tb drives into a big pool with the 20s; reason being is that raidz1 isn’t recommended for drives of that size. If 1 fails, resilvering to replace the failed drive will take a…

Two pools of 20 & 24tb drives?

TrueNAS General

SmallBarky July 11, 2025, 11:51pm 4

Have you verified those controllers and expansion card are recommendations?

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Two pools of 20 & 24tb drives?

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