Usable

The method backup software uses to calculate storage license capacity can vary depending on the software and the vendor. However, in general, the license capacity is based on the usable storage after deduplication and compression, as this is the storage required to store the backup data.

Some backup software vendors may use the front-end capacity (i.e., the amount of storage required before deduplication and compression) to estimate the needed usable storage. However, this is different from the basis for licensing capacity.

Backup software licensing can be complex. The license capacity may depend on the number of protected servers, backup agents, backup jobs, or the data being backed up. Therefore, reviewing the licensing agreement and consulting with the vendor is essential to ensure you understand the license capacity and any associated costs.

How has the license been calculated in Datadomain? Is it estimated/calculated frontend client-based or backend based on the storage? Is it based on the used capacity of the workloads in production storage (used size not provisioned) before dedupe and compression? For example, if I take 10TB client-based files after deduplication and compression is 5TB on the appliance storage, would the license cost be based on 10TB or 5TB? Based on the above concerns, what would you recommend when selecting any backup software?