Migrating a large DB without downtime using AWS DMS - by Vue.ai
Tech Talk on how Vue.ai migrated their PostgreSQL using AWS' DMS
A few weeks ago, I’d written a post on PostgreSQL’s awesome feature that allows streaming of change events from tables. Coincidentally, I ended up talking to engineers at Vue.ai who had used this exact same capability for a very cool use-case.
Vue.ai had to migrate a large PostgreSQL DB on AWS RDS from an old version to a new version. AWS allows you to upgrade your PostgreSQL RDS instance with a single click - the catch is that there’s downtime when the instance is unable to service or accept connections. That wouldn’t work for them.
They used AWS’ Data Migration Service (DMS). Under the covers, this involved using change events to logically replicate changes to the new instance, but it wasn’t all straightforward. They were kind enough to talk about it in detail. Here you go!