You can replace one disk at a time. I would practice with a vm first with a fresh mirrored install and then remove a disk and add another
There seem to be a lot of Linux centric tutorials out there but the commands should work fine
https://jordanelver.co.uk/blog/2018/11/26/how-to-replace-a-failed-disk-in-a-zfs-mirror/
There seem to be a lot of Linux centric tutorials out there but the commands should work fine
https://jordanelver.co.uk/blog/2018/11/26/how-to-replace-a-failed-disk-in-a-zfs-mirror/
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