I currently have a 9 disk RAID 10 setup. I plan on adding a 10th disk, but am waiting on a new SATA card to give me another data port.
At any rate, two of my drives are showing SMART errors, so I have a feeling that might be getting close to going. What I am wondering is how can I remove these and then replace them with two new drives? Do I need to remove one at a time, balance in-between, and then add the two new drives with a final balance? Or is there a command that I can run that would remove/add in one step?
I find it a bit hard to use. Be aware that if you are replacing with a larger disk, you will have to expand the new disk after replacing is done.
I have used the remove and add functions in the UI most of the times. Remove a drive from the pool, let the balance finish, disconnect it, connect the new drive, add it to the pool and let the balance finish. This is a slow process though.