Configuring a 125 TB Deduplication storage folder in Backup Exec

Last published : Apr 02, 2026
Backup Exec supports expansion of the Deduplication folder up to 125 TB. This section helps you to configure the 125 TB Deduplication storage folder in Backup Exec.
The maximum supported capacity of the Deduplication folder is 125TB out of which 20% is required for deduplication database and internal log processing. So effectively maximum 100 TB of backup data can be stored.
Minimum hardware requirements
  • CPU: A 64-bit processor with a minimum clock rate of 2.4-GHz is required. A minimum of 8 cores are required, 16 cores are recommended.
  • Memory: Minimum 125 GB. You may need to add more memory if you have additional roles performed by the same media server.
  • Storage:
    • Metadata disk: RAID 0+1 is recommended, with at least 1TB of space.
    • Data disks: It is recommended to have a maximum of five mount points. Each mount point must have a separate RAID group, a RAID 6 is recommended. Both the metadata disk and data disk must have more than 250 MB/sec of read or write speed.
    • Disks including more number of spindles provide better performance. Storage controller cache of minimum 2 GB or more is recommended.
Notes for configuring the 125 TB Deduplication storage folder
  • The Ransomware Resilience feature currently does not protect additional data partitions created using this configuration.
  • If you do not follow the settings, there can be performance issues as data may not be balanced optimally across all volumes.
  • Support for Deduplication folder size is up to 125 TB. The Deduplication folder can be of a smaller size and you can later add a maximum of five additional data partitions.
To configure 125 TB deduplication storage folder on a Windows server using 25 TB volumes
  1. Configure a Deduplication storage folder on local storage on Backup Exec server.
  2. Disable lockdown setting from the Backup Exec global settings.
Perform the steps in the order listed:
  • Click the Backup Exec button, select Configuration and Settings, and then selectBackup Exec Settings.
  • In the left pane, select Network and Security.
The Disk storage lockdown setting , is enabled by default.
  • Click Disable , to disable the setting.
At the prompt, enter the System Logon Account password and the reason for disabling the setting.
Note: Lockdown setting ensures that access to Backup Exec disk storage is limited only to authorized processes, such as Backup Exec services. Only Backup Exec is allowed to write to the disk storage. Lockdown is disabled to ensure that commands listed in the following step are allowed to temporarily write to the storage. To prevent data loss, this setting must be enabled as soon as the configuration is completed.
  1. Create data folder volumes under Deduplication storage as data1, data2, data3, data 4, data5 of 25 TB each.
Backup Exec qualified this solution only using NTFS volumes. Volumes must be mounted to an empty folder using disk management before running the following commands.
For more information about mounting a volume in an empty folder, refer to the following link:
https://docs.microsoft.com/en-us/windows-server/storage/disk-management/assign-a-mount-point-folder-path-to-a-drive
Perform the following in the order listed:
  • Create an etc directory and nbapp-release file using the following commands:
mkdir c:\etc
echo Windows_BYO > "c:\\etc\\nbapp-release"
  • Update DCHeaderHashSize setting in <Dedupe Storage DIR>\etc\puredisk\contentrouter.cfg to 2000000 / number_of_volumes.
For example, if you have five mount points, set DCHeaderHashSize to 400000.
  • Create Additional Data Partitions for Deduplication using the following command:
C:\Program Files\Veritas\Backup Exec>crcontrol.exe --dsaddpartition E:\BackupExecDeduplicationStorageFolder\data1
Run the earlier command for the remaining data partitions.
  1. After all the commands complete successfully, restart the Backup Exec services including the Deduplication services.
Additional Data mount points are available inside the Deduplication folder.
  1. Enable lockdown setting from the Backup Exec global settings.