Once it's detected, go back to the "USB Backup" page and it should be available
for further configuration
The USB hard disk(s) will be listed in the drop-down menu displaying the
remaining disk space. Make your selection from the drop-down menu if you have
more than one disks connected to the NVR.
Next, select channels, which you would like to backup the recording data from.
Maximum 4 channels can be selected at once
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