The Engine Yard Data Team shares in this blog post its the best practices for MongoDB. The team had assisted several customers with custom MongoDB environments and discovered during this process a variety of potentially problematic settings.
Its main recommendations are to test exhaustively within the context of the application and against conditions representative of your production system. Don’t assume that what worked for your RDBMS will work on MongoDB. You have to align realistic expectations with the features of the database. Consider the consistency and durability needs of your data as MongoDB offers durability through replication. It is never recommended to run a standalone MongoDB for production use, make sure you understand why.