Ceph Storage Quickstart
This guide will walk you through the basic setup of a Ceph cluster and enable you to consume block, object, and file storage from other pods running in your cluster.
Kubernetes v1.10 or higher is supported by Rook.
To make sure you have a Kubernetes cluster that is ready for
Rook, you can follow these instructions.
If you are using
dataDirHostPath to persist rook data on kubernetes hosts, make sure your host has at least 5GB of space available on the specified path.
If you’re feeling lucky, a simple Rook cluster can be created with the following kubectl commands and example yaml files. For the more detailed install, skip to the next section to deploy the Rook operator.
cd cluster/examples/kubernetes/ceph kubectl create -f common.yaml kubectl create -f operator.yaml kubectl create -f cluster-test.yaml
After the cluster is running, you can create block, object, or file storage to be consumed by other applications in your cluster.
For production environments it is required to have local storage devices attached to your nodes.
In this walkthrough, the requirement of local storage devices is relaxed so you can get a cluster up and running
as a “test” environment to experiment with Rook. A Ceph filestore OSD will be created in a
of requiring a device. For production environments, you will want to follow the example in
cluster.yaml instead of
cluster-test.yaml in order to configure the devices instead of test directories. See the Ceph examples for more details.
Deploy the Rook Operator
The first step is to deploy the Rook system components, which include the Rook agent running on each node in your cluster as well as Rook operator pod. Check that you are using the example yaml files that correspond to your release of Rook. For more options, see the examples documentation.
cd cluster/examples/kubernetes/ceph kubectl create -f common.yaml kubectl create -f operator.yaml # verify the rook-ceph-operator, rook-ceph-agent, and rook-discover pods are in the `Running` state before proceeding kubectl -n rook-ceph get pod
You can also deploy the operator with the Rook Helm Chart.
Create a Rook Ceph Cluster
Now that the Rook operator, agent, and discover pods are running, we can create the Rook Ceph cluster. For the cluster to survive reboots,
make sure you set the
dataDirHostPath property that is valid for your hosts. For more settings, see the documentation on configuring the cluster.
Save the cluster spec as
apiVersion: ceph.rook.io/v1 kind: CephCluster metadata: name: rook-ceph namespace: rook-ceph spec: cephVersion: # For the latest ceph images, see https://hub.docker.com/r/ceph/ceph/tags image: ceph/ceph:v14.2.1-20190430 dataDirHostPath: /var/lib/rook mon: count: 3 dashboard: enabled: true storage: useAllNodes: true useAllDevices: false # Important: Directories should only be used in pre-production environments directories: - path: /var/lib/rook
Create the cluster:
kubectl create -f cluster-test.yaml
kubectl to list pods in the
rook-ceph namespace. You should be able to see the following pods once they are all running.
The number of osd pods will depend on the number of nodes in the cluster and the number of devices and directories configured.
If you did not modify the
cluster-test.yaml above, it is expected that one OSD will be created per node.
$ kubectl -n rook-ceph get pod NAME READY STATUS RESTARTS AGE rook-ceph-agent-4zkg8 1/1 Running 0 140s rook-ceph-mgr-a-d9dcf5748-5s9ft 1/1 Running 0 77s rook-ceph-mon-a-7d8f675889-nw5pl 1/1 Running 0 105s rook-ceph-mon-b-856fdd5cb9-5h2qk 1/1 Running 0 94s rook-ceph-mon-c-57545897fc-j576h 1/1 Running 0 85s rook-ceph-operator-6c49994c4f-9csfz 1/1 Running 0 141s rook-ceph-osd-0-7cbbbf749f-j8fsd 1/1 Running 0 23s rook-ceph-osd-1-7f67f9646d-44p7v 1/1 Running 0 24s rook-ceph-osd-2-6cd4b776ff-v4d68 1/1 Running 0 25s rook-ceph-osd-prepare-node1-vx2rz 0/2 Completed 0 60s rook-ceph-osd-prepare-node2-ab3fd 0/2 Completed 0 60s rook-ceph-osd-prepare-node3-w4xyz 0/2 Completed 0 60s rook-discover-dhkb8 1/1 Running 0 140s
To verify that the cluster is in a healthy state, connect to the Rook toolbox and run the
ceph status command.
- All mons should be in quorum
- A mgr should be active
- At least one OSD should be active
- If the health is not
HEALTH_OK, the warnings or errors should be investigated
$ ceph status cluster: id: a0452c76-30d9-4c1a-a948-5d8405f19a7c health: HEALTH_OK services: mon: 3 daemons, quorum a,b,c (age 3m) mgr: a(active, since 2m) osd: 3 osds: 3 up (since 1m), 3 in (since 1m) ...
If the cluster is not healthy, please refer to the Ceph common issues for more details and potential solutions.
For a walkthrough of the three types of storage exposed by Rook, see the guides for:
- Block: Create block storage to be consumed by a pod
- Object: Create an object store that is accessible inside or outside the Kubernetes cluster
- Shared File System: Create a file system to be shared across multiple pods
Ceph has a dashboard in which you can view the status of your cluster. Please see the dashboard guide for more details.
We have created a toolbox container that contains the full suite of Ceph clients for debugging and troubleshooting your Rook cluster. Please see the toolbox readme for setup and usage information. Also see our advanced configuration document for helpful maintenance and tuning examples.
Each Rook cluster has some built in metrics collectors/exporters for monitoring with Prometheus. To learn how to set up monitoring for your Rook cluster, you can follow the steps in the monitoring guide.
When you are done with the test cluster, see these instructions to clean up the cluster.