I’m looking into moving our mlab instances over to atlas. There is a migration button I expect will do most of the work. However, will that remove what is currently live over on MLab?
I’d like to get Atlas set up, confirmed working, and then switch things over without losing my fallback.
Some of the migration outcomes depend on the type of clusters you are migrating from/to (for example, migrating between shared or dedicated clusters) but the general approach is to allow you to test and confirm your cutover to Atlas without removing any existing data from mLab.
Once you have finalised your migration to Atlas, you need to explicitly Delete the source mLab deployment to remove the data and stop any recurring charges.