HIKVISION iDS-9632NXI-I8/16S User Manual page 215

Step 3 Set the HDD property to R/W, Read-only or Redundancy.
Step 4 Click the OK button to save the settings and exit the interface.
Step 5 In the HDD Information menu, the HDD property will be displayed in the list.
At least 2 hard disks must be installed on your NVR when you want to set a HDD to Redundancy,
and there is one HDD with R/W property.
Network Video Recorder User Manual
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