What Is Replication? (+Differences Between Replication and Backup)

Zack Busch
Zack Busch  |  January 7, 2019

In the age of databases, servers and the internet, companies cannot afford to be offline — literally.

Business data transactions occur at all hours of the day, and downtime can be the difference between gains and losses in leads or profits. Services and transactions hinge on continuous, uninterrupted data accessibility. So, what do you do when downtime strikes? How do you recover if your servers tank? What happens to your data?

What is replication?

Replication in computing is more than just backup software. It also provides full-scale disaster recovery. Designed with the worst-case scenario in mind, replication is the continuous synchronization and maintenance of duplicate databases. These databases can be locally stored or remotely accessed, giving users flexibility in where and how they access their data.

Databases created during the replication process are designed to be immediate failovers. If one database goes down, the other databases are already synchronized with the most recent transactions from that downed database. Services that had been relying on the downed system continue to access data through the synchronized copies.

The key result of replication is fluid front-end use. Your users should never know a problem occurred, because they are shielded from back-end disruption. You never lose transactional data, because it is replicated through multiple databases. Your data is secure and your users continue uninterrupted. Everyone wins.

Replication can also serve as full-scale synchronization for multiple sources of database input. Users work on local copies of a database, and the database synchronizes with a central or master database. That master database then synchronizes other users’ local database copies, ensuring that once data is input, it exists on every user’s local copy. The end result is a unified data structure that keeps every user and every system on the same page at all times.

define-replication

Replication vs. backup

So…this is just continuous backup, right? Sort of. Like backup, replication backs up data in a way that can be recovered later. Replications are accessible and can be brought online as soon as they’re needed. But that description doesn’t quite do justice to replication software.

replication-vs-backup

Image via Zerto

The key difference between backup software and replication software is in the intended use. Backup software focuses on data restoration to a specific point in time. Backups are usually set up to run periodically (say, every morning and every evening), and they’re usually all-encompassing. That way, there’s always a “save point” that you can fall back on if something goes wrong.

Replication, on the other hand, focuses specifically on continued use. It is often offered as a DRaaS (disaster recovery as a service) solution. When outages occur, the primary concern is always, always getting core functionalities back online. This is what replication software is built for. It’s focused on only the most vital parts of a system, so that when an outage happens, the critical functions and data are still online and general operability continues.

Think of backup as picture taking and replication as video recording (or rather, recording several identical videos). Backups are snapshots of data taken at specific times every day, and data can be restored to its state at the snapshot time. Replication recordings all “roll” at the same time, so if one of the recordings goes down, the other recordings are exactly like the original and processing picks up where it left off.

Importance of replication

Every business that provides continuous data service should consider replication software as a disaster recovery option. While snapshot backups are great as fallbacks, replication is designed to provide up-to-date, perpetually-available data.

Entire industries hinge on this kind of availability. Health care EHR (electronic health record) accessibility is critical to treating patients in a timely, effective manner. e-commerce-focused companies quite literally cannot afford downtime because profits are driven digitally. Downtime in ERP systems (enterprise resource planning) can slow company functions like supply chain management and accounting to a crawl, greatly affecting production and distribution performance.

The importance of synchronized, identical databases should not be understated. You can avoid data discrepancies entirely because updates automatically synchronize every copy. Every user’s data synchronizes with both the master and with every other user’s data. You never have to worry about having old or outdated data again.


Next steps for protecting your files

Want to bring server replication down to a more individualized level? Check out hard drive cloning and how it might apply to your business.

Zack Busch
Author

Zack Busch

Zack is a Research Specialist who made the jump to the research realm after three years in IT support services. He studied mathematics, physics, and education at Truman State University. Zack enjoys video gaming, D&D, movies, TCGs, and spending time with his partner, dog, and two cats.