In a scenario I'm going to be up against, I'm going to have several backup jobs that have large Full Backups, but very small incremental jobs. Probably in the order of 4-6TB on average full backups, but nightly incrementals of about 2-3GB.
My question is this- Does what's on tape need to mirror the local storage in order to be recoverable? More specifically:
Say we have a 30 day retention for reverse incrementals. Our Full Backup file is 5TB, and eventually we'll have 30 incremental files. If I do a full tape backup of the directory, which would be the 5TB plus 30 incrementals, and from then on did an incremental tape job on only the incremental files, would that data still be recoverable?
To help answer that question, let's take a look at what the restored data might possibly look like after 90 days.
5TB Full backup file that was backed up originally 90 days ago
30 incremental backups that were backed up originally 90 days ago
60 incremental backups that were backed up over the course of 90 days
On my tape-restored data I technically have all incrementals since the last full. Would that still be recoverable data?