Dahua recorder reboots by itself again and again, what is behind it?

Repeated reboots usually mean a power or heat issue. Suspects are a tired power adapter, a recorder squeezed into a hot cabinet without airflow, or a failing hard disk. Dust and a swollen internal component are common on older units, and Dubai summers make it worse. We check adapter output, clean the unit, test the disk and improve ventilation. A bad main board generally means replacement.