Hi all, Just attempted to upgrade my Core install to Scale. After the upgrade, and logging in, my main Pool won’t mount and there is an error that states, " Disk(s): sdg, sdi, sdh, sdc, sdd, sde, sdb, sdf are formatted with Data Integrity Feature (DIF) which is unsupported." Is this a show stopper…

I may be talking crap here - but DIF is 520 byte sectors, rather than 512 byte sectors. This is configured / used by RAID cards (as far as I was aware), and not by “ZFS friendly” devices which suggests to me that you have a potentially major issue here - and not just with your upgrade to Scale. Ca…

Heya NugentS, So the drives are Hitachi 0F29530 HUH721212AL5200 12TB SAS. Capacity: 12TB Speed: 7.2K RPM Interface Types: SAS Form Factor: 3.5" LFF Hard Drive Sector Size: 512 / 512e Sustained Throughput: 243/255 Average Seek Time: 8.0/8.6 Electrical Interface: SAS-3 12Gbps On-Board Cache: …

Not a show stopper, have a few disks with this myself. You cannot add new DIF-formatted disks without reformatting them, but the ones added will continue to work.

Well there doesn’t seem to be anything wrong there. Just reformat them

Why do they work with TrueNAS Core though? What changed? Is it just the move from FreeBSD to Linux?

But the ones added don’t continue to work, they won’t mount.

New disks needs to be reformatted. All my old disks that was already in a pool works as expected.

Can confirm that doesn’t work. TrueNAS Scale refused to mount the pool at all.

How can I tell if my disks are setup this way? I don’t think they are, but I’m not sure…

These instructions should help: tales in IT from the help desk.: Formatted with Type 2 Protection, huh?

Tried to upgrade Core to Scale and received DIF error

TrueNAS General

LarsR May 13, 2026, 9:55am 13

From another Forum post it may be that CE (and any scale version before) don’t have the kernel module needed for DIF to work, but it’s in the bsd kernel of core. At least that’s how i understood it from

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Tried to upgrade Core to Scale and received DIF error

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