Cloud Storage with Red Hat Ceph Storage
In this chapter, you learned:
The two main components of the cephadm utility:
The
cephadm shellruns a bash shell within a specialized management container. Use the cephadm shell to perform cluster deployment tasks and cluster management tasks after the cluster is installed.The
cephadm orchestratorprovides a command-line interface to the orchestrator ceph-mgr modules. The orchestrator coordinates configuration changes that must be performed cooperatively across multiple nodes and services in a storage cluster.
As of version 5.0, all Red Hat Ceph Storage cluster services are containerized.
Preparing for a new cluster deployment requires planning cluster service placement and distributing SSH keys to nodes.
Use cephadm to bootstrap a new cluster:
Installs and starts the MON and MGR daemons on the bootstrap node.
Writes a copy of the cluster public SSH key and adds the key to authorized keys file.
Writes a minimal configuration file to communicate with the new cluster.
Writes a copy of the administrative secret key to the key ring file.
Deploys a basic monitoring stack.
Use the
cephadm-preflight.ymlplaybook to verify cluster host prerequisites.Assign labels to the cluster hosts to identify the daemons running on each host. The
_adminlabel is reserved for administrative nodes.Expand cluster capacity by adding OSD nodes to the cluster or additional storage space to existing OSD nodes.
