Quick Look: What is Replication?

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I've talked a few times about backups and one common word that comes up when talking about backups is replication. Well, what is Replication and how does it differ from backups? Replication is the process of duplicating all data to another source in real-time, or near real-time. It's very different than backups. Let's look at why.

What's confusing is that Replication and Backups (of the Full, Differential or Incremental kind) are just part of a backup or disaster-recovery plan. Replication doesn't prevent against data corruption or deletions. If you backed up a folder of data, the backup would copy all of that data. If you then removed half of those files and backed it up again, the new backup would still have a copy of the data you deleted. In that same scenario, replication would've already over-wrote the target with the files on the source (deleted files and all).

Replication is a great tool in your Business-Continuity/Disaster-Recovery Arsenal but it's not the only one. Used in conjunction with a backup strategy, it can overcome a lot.

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