# How to Keep Data Safe During a Site Failover

> A method for keeping data backups synchronized and accessible even when a primary data center goes offline and systems must switch to a backup location.

- **Patent:** US 9672117
- **Original title:** Method and system for star replication using multiple replication technologies
- **Owner:** EMC IP Holding Co LLC
- **Granted:** 2017
- **Status:** Active
- **Times cited:** 21
- **Field:** software, telecommunications, consumer_electronics

## What it does

This patent describes a way to manage data recovery when a primary production site fails. It uses a star-like topology where data is replicated to a secondary site and backed up to a separate storage location. When a failover occurs, the system reverses the flow of data, treating the replication site as the new production site. It uses a delta marker stream to track differences between storage locations, ensuring that the backup site remains consistent with the new production state even during complex recovery operations.

## What it does NOT cover

- Does not cover simple data mirroring without a failover mechanism.
- Does not cover data backup methods that lack a delta marker stream for tracking changes.
- Does not cover cloud-native object storage replication that does not involve a site-based failover.
- Does not cover hardware-agnostic data recovery that ignores the state of the production site storage.

## The clever bit

The system uses a unified delta marker stream to manage differences across multiple storage tiers during a failover, effectively 'reversing' the replication logic to maintain data integrity without manual intervention.

## Real-world examples

1. Dell EMC RecoverPoint
2. Enterprise disaster recovery storage clusters
3. Multi-site data center synchronization systems

## Why it matters

In enterprise IT, maintaining business continuity is critical. This patent provides a specific orchestration logic for EMC's (now Dell Technologies) data protection ecosystem, ensuring that when a disaster occurs, the backup chain does not break. It is a foundational piece of logic for high-availability storage arrays used by large corporations to prevent data loss during site outages.

## Frequently asked questions

### What does How to Keep Data Safe During a Site Failover cover?

A method for keeping data backups synchronized and accessible even when a primary data center goes offline and systems must switch to a backup location.

### Who owns patent US 9672117?

EMC IP Holding Co LLC owns this patent, granted in 2017.

### When does this patent expire?

This patent is expected to expire on June 6, 2037, when the invention enters the public domain.

### What is patent US 9672117 cited by?

This patent has been cited by 21 later patents that build on its ideas.

### What problem does this patent solve?

In enterprise IT, maintaining business continuity is critical. This patent provides a specific orchestration logic for EMC's (now Dell Technologies) data protection ecosystem, ensuring that when a disaster occurs, the backup chain does not break. It is a foundational piece of logic for high-availability storage arrays used by large corporations to prevent data loss during site outages.

### What does this patent NOT cover?

Does not cover simple data mirroring without a failover mechanism.

**Full plain-English explainer:** https://patentbrief.org/patent/us/9672117/aws-codedeploy

**Original patent:** https://patents.google.com/patent/US9672117

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_Source: PatentBrief — https://patentbrief.org. Patent facts are from public records; the plain-English explanation is PatentBrief's._