What is database replication, and how can it be used for fault tolerance?

Database replication implies the replication of data across multiple instances of the same database. In this scenario, there is usually one database that’s acting as a master to all clients that are connecting it, and the rest act as “slaves” where they simply receive updates on the data being changed/added. The two main implications of this in fault tolerance are: - A database cluster can withstand problems on the master server by promoting one of the slaves without losing any data in the process. - Slaves can be used as read-only servers, increasing the amount of read requests that can be performed on the data without affecting the performance of the database.

databases scaling