Summary
In this chapter, you learned that MongoDB replica sets are essential for providing high availability and load sharing in a MongoDB database environment. While Atlas transparently provides support for infrastructure and software (including for replica set cluster management), not all MongoDB clusters are deployed in Atlas. In this chapter, we discussed the concepts and operations of replica set clusters. Learning about simple concepts for clusters, such as read preference, can help developers build more reliable, high-performance applications in the cloud. In the next chapter, you will learn about backup and restore operations in MongoDB.