In some cases the rebuild of the RAID might not start automatically. If you encounter this you may set the new drive as a spare disk first. The rebuild will start immediately after this is done.
To set the new drive as a spare disk, please follow the steps below:
Log in to your NAS via web browser
Open Storage & Snapshots
Go to Storage > Storage/Snapshots
Select your Storage Pool or Static Volume and click on the “Manage” button
Select the degraded RAID group section and click “Manage” and then “Configure Spare Disk”.
Select the new drive and click Apply
試試把新碟"設定為備用磁碟".
唔得快backup, call support.可能個raid config file corrupted.