Dell EMC Data Domain

Data Domain is Dell's deduplication storage line for backup and long-term retention, now sold under the PowerProtect DD name, with both names used across the vendor's own material. It applies inline deduplication so that repeated data is stored once, reducing the physical capacity a backup estate requires and the bandwidth needed to replicate it offsite.

Deduplication ratios are the number these systems are sold on and the one to interrogate. Backups are extraordinarily repetitive, since most of a system is unchanged between one backup and the next, so high ratios are genuinely achievable and depend entirely on the data and the retention policy rather than on the appliance alone.

Replication bandwidth is the benefit that is easier to overlook and often larger. Sending only changed unique blocks to a second site means an offsite copy becomes feasible over a link that could never carry full backups, which changes what disaster recovery an organisation can afford.

The naming should be understood before searching for support material. Data Domain is the established name and PowerProtect DD is the current one, and documentation, forums and job listings all use both interchangeably, so a search on either name finds only part of what exists.