Trouble migrating data to new ZFS pool
from priapus@sh.itjust.works to homelab@lemmy.ml on 05 Mar 2025 01:50
https://sh.itjust.works/post/33819825

I am upgrading my drives and have created a new pool. The original pool had a drive fail, but it has since been replaced. Each drive CKSUM value is at 4.04k and pool had two files with permanent errors. I deleted those, but it now shows this:

errors: Permanent errors have been detected in the following files:

        zfsa:<0x8220>
        zfsa:<0x8056>

When I try to create a snapshot and send it to the new pool. After a few terabytes, it fails with this error warning: cannot send ‘zfsa@zpool_transfer’: insufficient replicas.

CKSUM was always at zero until the first drive failed. The data is not important and I don’t care about whatever is corrupt, I just want to get the data to the new pool.

Edit: Forgot to mention, I have scrubbed the pool many times.

Another edit: I’ve also tried using zpool clear as well. Despite the high checksum errors I’ve had no issues outside the two now deleted files. The pool is used for a media server which has been working perfectly.

After I scrub the checksum errors go to zero, but they start climbing when I run the send/receive.

Edit:

Finally remembered to come edit this post with the solution I got from the Practical ZFS forums. Thanks to Jim Salter over there for the solution!

You can bypass the checks by settings a ZFS module parameter. A way to do this temporarily is with echo 1 > /sys/module/zfs/parameters/zfs_send_corrupt_data, which will last until you reboot. After doing this, sending the data, and a scrub, everything was fine!

#homelab