Commvault Backup Options

Hi,

That won't work under the hood. Due to the built-in software deduplication, the system breaks data down into millions of small chunks rather than structured .bak files, meaning there is no distinct file-level separation between fulls and incrementals.

Ideally, we'd handle this via mixed retention on a single copy (e.g., 14 days immutable, transitioning to non-immutable for the rest of the month to save costs), which is a feature I've requested in the past, but as of now technically it won’t be possible. 

As it stands, the only workaround is to split this into two separate copies: a standard non-immutable copy for daily backups, and a separate immutable copy for e.g. weekly fulls. Unfortunately, because of the two sets of data involved, this approach won't offer the cost optimization you are looking for.

While you could conceivably use the “Incremental Storage Policy” feature to separate your Full and Incremental backup data, any level of cost optimisation would be highly dependent on your retention requirements.