Because server capacity is finite, local backup data obviously cannot be stored indefinitely. That’s where retention scheduling comes in. Carbonite offers flexible retention scheduling, giving users the ability store backup data in ways that meet specific business or compliance needs.
To understand how retention scheduling works, it helps to first look at how backups are performed. Carbonite Server takes “forever incremental” backups. This means that an initial full backup of a given data set is taken, and all subsequent backups are incrementals (only changes since the last backup are copied).
Users can use our standard retention schedule for incrementals or opt to customize retention. Let’s look at an example of standard retention:
Backup schedule: Hourly
Retention schedule: Standard (incremental backups are merged once a day, for seven days)
- A full backup is taken, then subsequent incremental backups occur hourly.
- On Day 3 of the backup job, hourly incremental backups from Day 1 are merged into a single daily backup and redundant data is purged; on Day 4, the hourly backups from Day 2 are merged; and so on. The process continues for seven days.
- On Day 8, the merged incremental backup from Day 1 is purged.
This retention schedule ensures that you always have an up-to-date copy of data for operational recovery. However, it does not preserve older backups for archival purposes. If you need to maintain older backup data, Carbonite Server gives you the option to select a grandfather-father-son (daily/weekly/monthly) structure long-term archiving. Let’s take a look at how it works:
Backup schedule: Hourly
Retention schedule: Custom (grandfather-father-son incremental merge)
Daily: Follows the same pattern as standard retention.
Weekly: Daily merged incrementals are merged into a single weekly incremental. User selects the day to perform merge.
Monthly: Weekly merged incrementals are merged again into a monthly. User selects a particular day in a month (e.g.: Third Wednesday) to perform the merge.
Additionally, users can configure local and cloud retention settings independently. In other words, you might choose to purge incrementals on the backup server while retaining them in the cloud. This could be used to meet compliance regulations that require data to be stored for a specific period of time, (e.g. HIPAA compliance).