cephadm

container-based Ceph cluster deployment

TLDR

Bootstrap a new Ceph cluster

$ sudo cephadm bootstrap --mon-ip [monitor_ip]

Add a new host to the cluster

$ sudo cephadm add-host [hostname] [ip_address]

Deploy a specific service

$ sudo cephadm deploy [service_type] --name [service_name]

Check status of cluster services

$ sudo cephadm shell -- ceph -s

Enter a shell inside the Ceph container

$ sudo cephadm shell

Remove a service from the cluster

$ sudo cephadm rm-service [service_type] --name [service_name]

SYNOPSIS

cephadm [options] command [arguments]

cephadm deploys and manages Ceph distributed storage clusters using containers (Podman preferred, Docker supported). It is the modern orchestration tool for Ceph, replacing older deployment methods like ceph-deploy and ceph-ansible.The tool handles the complete cluster lifecycle: bootstrapping a new cluster on a single node, adding hosts, deploying daemons (monitors, OSDs, managers, gateways), and upgrading the cluster. Each Ceph daemon runs in its own container, providing isolation and simplified upgrades.The `bootstrap` command creates an initial single-node cluster with a monitor and manager, generates admin credentials, and sets up the orchestrator for subsequent operations. The `shell` command provides an interactive environment inside a Ceph container with all management tools available.

PARAMETERS

--mon-ip ip

Monitor IP address for bootstrap

--cluster-network CIDR

Restrict the OSD replication network to the given subnet.

--ssh-user USER

User cephadm should SSH to remote hosts as (default `root`).

--initial-dashboard-user, --initial-dashboard-password

Credentials for the Ceph Dashboard created during bootstrap.

--skip-dashboard

Do not enable the dashboard.

--fsid UUID

Reuse an existing cluster FSID instead of generating one.

--name name

Service or daemon name

--image image

Container image to use

--docker

Force the use of Docker instead of Podman.

-v, --verbose

Increase logging verbosity.

SUBCOMMANDS

bootstrap

Initialize a new Ceph cluster

add-host

Add a host to the cluster

rm-host

Remove a host from the cluster

deploy

Deploy a daemon

rm-daemon

Remove a daemon

shell

Enter interactive shell in Ceph container

enter

Run a command inside an existing Ceph container

List all Ceph daemons running on this host

Show status of daemons (alias of `ls --no-extra-info`)

check-host

Verify host prerequisites (packages, time sync, container runtime)

prepare-host

Install missing prerequisites

gather-facts

Collect host inventory information

adopt

Adopt a daemon from a legacy (non-cephadm) deployment

logs

View daemon logs

rm-cluster

Destroy the local cluster state (dangerous)

INSTALL

sudo apt install cephadm

sudo dnf install cephadm

sudo apk add ceph18-cephadm

sudo zypper install cephadm

CAVEATS

Requires container runtime (Podman preferred, Docker supported). Bootstrap creates initial admin credentials. Services are managed through the orchestrator, not directly.