cephadm utility

The cephadm utility deploys and manages a Ceph storage cluster. It is tightly integrated with both the command-line interface (CLI) and the IBM Storage Ceph Dashboard web interface so that you can manage storage clusters from either environment. cephadm uses SSH to connect to hosts from the manager daemon to add, remove, or update Ceph daemon containers. It does not rely on external configuration or orchestration tools such as Ansible or Rook.

Note: The cephadm utility is available after running the preflight playbook on a host.

The cephadm utility consists of two main components:

  • The cephadm shell.

  • The cephadm orchestrator.

The cephadm shell

The cephadm shell starts a bash shell within a container. Use the shell to complete “Day One” cluster setup tasks, such as installation and bootstrapping, and to use ceph commands.

For more information about how to start the cephadm shell, see Using the cephadm shell.

The cephadm orchestrator

Use the cephadm orchestrator to perform “Day Two” Ceph functions, such as expanding the storage cluster and provisioning Ceph daemons and services. You can use the cephadm orchestrator through either the command-line interface (CLI) or the web-based IBM Storage Ceph Dashboard. Orchestrator commands take the form ceph orch.

The cephadm script interacts with the Ceph orchestration module that is used by the Ceph Manager.