MongoDB replica set to stand alone backup and restore

Question

For development reasons, I need to backup a production replica set mongodb and restore it on a stand alone, different machine test instance.

Some docs are talking about the opposite ( standalone 2 replica-set ), but I cannot find his downgrade/rollback way.

What's the way to go, in this case ?

Answer 1

No matter how many nodes you have in a replica set, each of them holds the same data.

So getting the data is easy - just use mongodump (preferably against the secondary, for performance reasons) and then mongorestore into a new mongod for your development stand-alone system.

mongodump does not pick up any replication related collections (they live in database called local). If you end up taking a file system snapshot of a replica node rather than using mongodump, be sure to drop the local database when you restore the snapshot into your production stand-alone server and then restart mongod so that it will properly detect that it is not part of a replica set.