Database Reference
In-Depth Information
High availability
We will discuss availability in the next chapter. For now, assume availability is the probab-
ility that we query and the system just works. A high-availability system is one that is
ready to serve any request at any time. High availability is usually achieved by adding re-
dundancies. So, if one part fails, the other part of the system can serve the request. To a cli-
ent, it seems as if everything works fine.
Cassandra is a robust software. Nodes joining and leaving are automatically taken care of.
With proper settings, Cassandra can be made failure-resistant. This means that if some of
the servers fail, the data loss will be zero. So, you can just deploy Cassandra over cheap
commodity hardware or a cloud environment, where hardware or infrastructure failures
may occur.
