In this chapter, we learned about Ceph's internal components, including objects, the CRUSH algorithm, placement groups, and pools, and how they interact with each other to provide a highly reliable and scalable storage cluster. This chapter is based on the practical approach for these components so that you can understand each bit of it. We also demonstrated how data is stored in the cluster, right from the point when it enters as a write request to a Ceph pool until it reaches the correct OSD filesystem and is stored in the form of an object. We recommend you repeat these practical examples on your test cluster; this will give you a broader view of how Ceph stores your data in a highly replicated, readily available form. If you are a system admin, you should focus more on discovering Ceph pools and CRUSH maps as mentioned in this chapter. This is something that is expected from a system admin both before and after cluster provisioning. In the next chapter, we will learn about Ceph cluster hardware planning and its various installation methods, followed by upgrading the Ceph cluster version and scaling it up.