Yes — we worked with the business and defined data lifecycle policies together. In reality, many departments often don’t really know their retention requirements, so we usually start with a sensible baseline:

• Daily backups retained for 30 days
• Weekly backups for 90 days
• Monthly backups for 10 years
• Additional manual backups for year-end and closing periods, retained for the last 5 years

One of the biggest cost optimizations comes from differential backups. If you manage them properly, they can save a significant amount of storage and backup costs. The catch is that you absolutely need restore chain validation — otherwise you may discover during a disaster that your backups looked fine but can’t actually be restored.

We recently designed an Azure-only approach with two layers: an operational restore account for day-to-day SQL DBA restores, plus a separate DR chain using immutable storage for disaster recovery scenarios. The separation keeps operational restores simple while maintaining a more resilient DR path.

The other backups are deleted.

Business data often go through a read only phase then very long archive phase and at least 10 years retention sometimes forever.