Hello,

I have 2 nvme 1tb drives in a zfs mirrored pool. I'd like to replace them with 4tb drives. What would be the best way to go about that? They are where my docker and VMs reside. Is it just as simple as swapping one, let it rebuild then swapping the other? Thanks!

Edited December 7, 2025Dec 7 by impenetrable-aviator2287

5 hours ago, impenetrable-aviator2287 said:

Is it just as simple as swapping one, let it rebuild then swapping the other?

Typically yes, replace the first, wait for the resilver to finish, replace the second one, the pool will expand.

On 12/7/2025 at 4:01 AM, JorgeB said:

Typically yes, replace the first, wait for the resilver to finish, replace the second one, the pool will expand.

So I replaced 2 1TB Crucial T705 nvme drives for 2 4TB Crucial T710 drives and they both were in a ZFS mirror. Both 4TB drives failed within 2 weeks of being put in. Am I just unlucky or should I not be using these in a mirrored pool?

If you didn't reboot after the errors, post the diags, it may not be a device problem.

20 hours ago, JorgeB said:

If you didn't reboot after the errors, post the diags, it may not be a device problem.

Diags as requested.

fileserver-diagnostics-20251226-0023.zip

Dec 24 21:57:56 Fileserver kernel: nvme nvme0: Disabling device after reset failure: -19

Nvme device dropped offline, you can try this:

on the main GUI page click on the flash drive, scroll down to "Syslinux Configuration", make sure it's set to "menu view" (top right) and add this to your default boot option, after "append initrd=/bzroot"

nvme_core.default_ps_max_latency_us=0 pcie_aspm=off pcie_port_pm=off

e.g.:

append initrd=/bzroot nvme_core.default_ps_max_latency_us=0 pcie_aspm=off pcie_port_pm=off

Reboot and see if it makes a difference.

Thanks Jorge, will this bring the offline device back? Or has Unraid blocked it for good?

Looks like it didn't come back after rebooting. So guessing it's blacklisted by the OS.

You may need to power cycle the server, just a reboot may not be enough if the device is still offline.

7 hours ago, JorgeB said:

You may need to power cycle the server, just a reboot may not be enough if the device is still offline.

I'll try that, but when it came back up after a reboot, the drive was no longer available to be selected. It just stated "no device".

Shutdown and verified the bios saw the drive and booted up fully. Drive showed up and let it resilver. Will monitor it to see if it will drop out again. Thanks for the help Jorge! I'll let you know if I run into any snags.