Add 3rd disk to existing mirror -- "Add to Pool" or "Extend vDEV"

[SmallBarky]

Isn’t it in Fangtooth?

[Accepted] Create 2 GiB buffer space when adding a disk

Problem/Justification When replacing a drive in a vdev, a new drive even from the same manufacturer may just be a hair too small to fit the vdev. Examples of users impacted by the recent change in SCALE 24.04.1 to remove the default 2 GiB swap partition, which acted as this buffer: Impact With a default buffer space of 2 GiB, a slightly-too-small replacement drive could still be added with a smaller or no buffer on that drive. FreeNAS, TrueNAS CORE and TrueNAS SCALE before 24.04.1 did t…

https://ixsystems.atlassian.net/browse/NAS-134309