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QuTS hero 5.0.x

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Configuring the Backup Battery Unit (BBU) Settings

You can schedule a learning cycle for the backup battery units (BBUs). A learning cycle is when a controller performs a battery calibration operation to determine the battery's condition. During this cycle, the system switches to write-through mode to protect data integrity.

In write-through mode, the NAS writes data directly to HDDs/SSDs instead of writing to the RAM first. This prevents data loss if a power outage occurs before the NAS finishes writing data.

This function is only available for models with redundant power supply units.


QNAP strongly recommends scheduling the learning cycle during off-peak hours.

  1. Go to Control Panel > System > Hardware > BBU.
  2. Select Enable BBU learning schedule.
  3. Specify a learning cycle schedule.
  4. Click Apply All.