Migrations

No Downtime Database Migrations

Introduction

Back at my last job, we successfully migrated from MongoDB to Cassandra without any downtime. We did two webinars with Datastax at the time (I am now a Datastax employee). Our first webinar was a general overview on the migration. The second, we covered some of the lessons we learned after being in production with Cassandra for a while. We touched on our migration process, but didn’t get deep into the details. This post will discuss the strategy, it’s goals, and what we learned along the way. The strategy applies to any database migration, and is not scoped only to moving between databases either.