When a drive is un-mounted or disconnected, the DNR-202L will beep and continue recording to the second disks automatically if one is available, and the DNR-202L will beep until HDD button is pressed once.
Note:
HDD 1 Button: Press this button to release the HDD attached to the USB Port for HDD 1.
HDD 2 Button: Press this button to release the HDD attached to the USB Port for HDD 2.