How Forever Incremental Backup Changed the World
Forever incremental backup technology has completely transformed how we protect data. It eliminated the need for regular full backups, solved major performance headaches, and dramatically reduced storage requirements – all while improving restore times. What’s not to love?
This blog post summarizes the main points of my latest podcast episode. If you’d like, you can listen to it or watch it at https://www.backupwrapup.com/)
The Problem with Traditional Backup Methods
Remember the bad old days? We’d do weekly full backups followed by daily incrementals. Those weekly fulls would crush your systems, saturate your networks, and consume massive amounts of storage. And then we’d do it all over again the next week! It was inefficient and painful, but we didn’t have better options.
The traditional approach created tons of duplicate data. If you were doing weekly fulls with 90-day retention, you’d end up with 13 copies of data that mostly hadn’t changed. Even with a typical change rate of 2% daily or 7-8% weekly, we were repeatedly backing up the same unchanged data.
When virtualization came along, this approach completely broke down. Suddenly those 20 individual machines became 20 VMs all running on the same physical hardware. Trying to do simultaneous full backups across multiple VMs on the same host? Recipe for disaster.
The Forever Incremental Revolution
Forever incremental backup represents a fundamental redesign of how backup works. Instead of repeated full backups, you do one initial full backup followed by incremental backups forever. But here’s the key difference from traditional incrementals: each recovery point behaves like a full backup during restore.
In a true forever incremental system, you’re not just tracking file-level changes, but block-level changes. This further reduces the amount of data transferred across the network during backups. When VMware introduced Change Block Tracking (CBT), it made forever incremental backups even more efficient for virtual environments.
Why Forever Incremental Is Superior
The benefits of forever incremental backup include:
- Eliminated backup windows: No more weekend-crushing full backups
- Reduced network traffic: Only changed blocks travel across the network
- Lower storage requirements: No redundant copies of unchanged data
- Faster restores: No need to apply multiple incrementals during recovery
- Reduced impact on production systems: Only scanning for changes, not full content
The Technology Behind Forever Incremental
For forever incremental backup to work properly, you need two key components:
- A way to efficiently track changed blocks or files
- A storage system that can maintain multiple recovery points
This is why disk became essential for true forever incremental systems. The original attempt at forever incremental was IBM’s TSM (now Spectrum Protect), but it used tape as the storage medium. The result? Restores that required hundreds or thousands of tapes, making recovery painfully slow.
Modern solutions like Rubrik, Cohesity, and cloud-native backup services implement forever incremental with disk-based storage and deduplication. This combination creates the perfect environment for efficient forever incremental backups.
Is Everyone Using Forever Incremental?
Despite its clear advantages, not every environment has adopted forever incremental backup. Why?
- Backup is sticky: Many organizations are still running the same backup software they’ve used for 15+ years
- Application support: Not all applications provide the APIs needed for efficient incremental backup
- Mixed environments: Organizations often run multiple backup solutions for different workloads
If you’re still doing traditional full and incremental backups, it might be time to consider modernizing your approach. The benefits of forever incremental backup are too significant to ignore.
The Future of Backup
Forever incremental has become the standard for modern backup solutions. When you look at newer products that have emerged in the last decade, they all implement some form of forever incremental technology.
While databases and some applications still require regular full backups, the trend is clearly moving toward solutions that minimize data transfer, storage requirements, and restore complexity. Forever incremental is no longer just a nice feature – it’s a fundamental requirement for any serious backup solution.
Written by W. Curtis Preston (@wcpreston), four-time O'Reilly author, and host of The Backup Wrap-up podcast. I am now the Technology Evangelist at S2|DATA, which helps companies manage their legacy data