I just moved from my main pool having 2 disks to 4 disks. I documented every single step and verified it works flawlessly by doing it a second time. This could save you hours if you are running the latest release because it talks about all the “gotchas” caused by bugs in the latest version of Scale…

[image] stk: moved from my main pool having 2 disks to 4 disks. I documented every single step and verified it works flawlessly by doing it a second time. This could save you hours if you are running the latest release because it talks about all the “gotchas” caused by bugs in the latest versio…

Yes, I read that before I did the process. But it didn’t apply to me since I had a 2 disk mirror. The process I described is basically the correct path to reconfigure an existing pool to add more drives.

Why did you not add another mirror vdev to the existing pool? That’s perfectly supported and done in a few clicks.

because I get 30 Tb available instead of 20TB.

RAID-Z pool expansion by drive is slated for inclusion in Electric Eel in October 24.10 (Electric Eel) Development Notes Highlights, change log, and known issues for the latest SCALE nightly development version.

i’ll tell my buddy. he is still stuck on qnap. he said he needed this before he could make the switch like i did :smiling_face_with_three_hearts:

Thanks for the detailed migration process. I did my migration using your instructions (updated the whole pool) and it went flawlessly. :muscle: :ok_hand:

Yes. See pics in this thread: [image] RaidZ Expansion on ElectricEel Nightlies TrueNAS General Hello! Support for RaidZ Vdev Expansion is now available in ElectricEel Nightlies. For those who do not know its a new feature that allows to extend an existing raidz vdev wit…

Hi there, I just wanted to thank the OP @stk for this detailed guide, as it allowed me to migrate my 4-disk wide RAID-Z2 pool to a backup RAID-Z1 pool (1-disk wide, through USB, not recommended, I know…), and back to a new pool, comprising the original 4 hard drives with 2 extra hard drives (6-disk …

SOLVED: Step-by-step process to migrate or upgrade a pool, e.g., 2 disks --> 4 disks

TrueNAS General

DjP-iX April 29, 2024, 6:14pm 6

RAID-Z pool expansion by drive is slated for inclusion in Electric Eel in October

QNAP TS-877 Truenas Journal

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6 Disks...(2) 3 disk Raid-Z1 or (1) 6 disk Raid-Z2? TrueNAS General	12	3582	October 16, 2024
Advice for pool migration - new hard drives TrueNAS General SCALE , ZFS	17	278	March 14, 2026
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SOLVED: Step-by-step process to migrate or upgrade a pool, e.g., 2 disks --> 4 disks

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