Where the function is intended for
A recorder can overwrite images when the storage period has been reached, or may not overwrite new images if a disk status requires attention.
advice
Check Dahua NVR disk status
The hard disk is a central part of local recording; a green live image says nothing about the health or space of the recording storage.
Setting or condition
Check the disk status in the recorder, the assigned recording channels, and whether there are any notifications or exceptions. Look at the desired storage period instead of just looking at a percentage bar.
Making a conscious choice
First investigate the cause and data risk before you format or replace. Choose storage capacity based on the cameras, recording profile, and the actual desired viewing period.
What you check afterwards
Retrieve recent and older recordings and check whether the recorder continues to write new images. Note disk changes and date in the system file.
Frequently asked questions
Is a full disk always broken?
No. Transferring can be normal behavior, depending on the settings.
May I just format a disk?
Not before you have assessed which images and settings are disappearing as a result.