Whether you have a small, medium, or exascale cluster, monitoring is the most critical part of your infrastructure. As soon as you have done the designing, deployment, and production service implementation of your Ceph cluster, monitoring becomes the key responsibility of the storage administrator. In this chapter, we will learn multiple ways to monitor your Ceph cluster and its components. We will cover both the CLI and GUI monitoring of Ceph using its native CLI tools; we will also implement Calamari, which is an open source Ceph cluster management dashboard.