> you don't expect your collection to retain long-gone files unless it's an ever-growing pile of tapes/discs.
Rule number whatever of backups: Don't discard old backups. Bitrot occurs, and people make mistakes, and newer backups can have flaws that older ones don't, which will go undiscovered until it's too late.
We're not talking about piles of tapes, we're talking about virtually unlimited disk space. State-of-the-art backup software chunks and deduplicates data and stores snapshots of directory trees. For most cases, there's no reason not to keep a subset of old snapshots, and many reasons to keep them.
Rule number whatever of backups: Don't discard old backups. Bitrot occurs, and people make mistakes, and newer backups can have flaws that older ones don't, which will go undiscovered until it's too late.
We're not talking about piles of tapes, we're talking about virtually unlimited disk space. State-of-the-art backup software chunks and deduplicates data and stores snapshots of directory trees. For most cases, there's no reason not to keep a subset of old snapshots, and many reasons to keep them.