As a system grows, or an application gets matured, or the cloud infrastructure starts to warn of failure of the underlying hardware, or probably you have got hit by the TechCrunch effect, you may need to do one of these things: repair, backup, or scale up/down. Or, perhaps, the management decides to have another data center set up just for analysis of data (maybe using Hadoop) without affecting the user's experience for which the data is served from the existing data center. These tasks come as an integral part of a system administrator's day job. Fortunately, all these tasks are fairly easy in Cassandra and there is a lot of documentation available for it.
In this chapter, we will go through Cassandra's built-in DevOps tool and the discuss on scaling a cluster up and shrinking it down. We will also see how one can replace a dead node or just remove it, and let other nodes bear the extra load. Further, we will briefly see backup...