The system disk migration feature is currently in beta and cannot fulfill your requirement at this time. For your scenario, you will need to reconfigure Emby - please note this process won't affect any data stored in your existing shared folders. Please follow this procedure:
1. After logging into TOS, insert your new HDD. Navigate to Control Panel > Volume to create a new volume, selecting "Create new storage pool" using the newly installed drive.
2. Go to Control Panel > Shared Folders to establish new shared folders, ensuring they're created on the new volume from your additional HDD.
3. Use TFM Backup utility to create a backup task, transferring your data to the newly created shared folders.
4. After successful backup, power down the system. Insert the disk containing your new volume, then reinstall the system using Method B as detailed in our guide:
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5. Upon successful OS installation, reinstall and configure Emby.
6. Finally, insert your second new HDD to create additional volumes and shared folders for expanded storage.