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 v1.11 or higher is supported by Rook.
Important If you are using K8s 1.15 or older, you will need to create a different version of the Rook CRDs. Create the
crds.yaml found in the pre-k8s-1.16 subfolder of the example manifests.
To make sure you have a Kubernetes cluster that is ready for
Rook, you can follow these instructions.
In order to configure the Ceph storage cluster, at least one of these local storage options are required:
- Raw devices (no partitions or formatted filesystems)
- Raw partitions (no formatted filesystem)
- PVs available from a storage class in
You can confirm whether your partitions or devices are formatted filesystems with the following command.
lsblk -f NAME FSTYPE LABEL UUID MOUNTPOINT vda └─vda1 LVM2_member eSO50t-GkUV-YKTH-WsGq-hNJY-eKNf-3i07IB ├─ubuntu--vg-root ext4 c2366f76-6e21-4f10-a8f3-6776212e2fe4 / └─ubuntu--vg-swap_1 swap 9492a3dc-ad75-47cd-9596-678e8cf17ff9 [SWAP] vdb
FSTYPE field is not empty, there is a filesystem on top of the corresponding device. In this case, you can use vdb for Ceph and can’t use vda and its partitions.
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.
git clone --single-branch --branch v1.5.1 https://github.com/rook/rook.git cd rook/cluster/examples/kubernetes/ceph kubectl create -f crds.yaml -f common.yaml -f operator.yaml kubectl create -f cluster.yaml
After the cluster is running, you can create block, object, or file storage to be consumed by other applications in your cluster.
The Rook documentation is focused around starting Rook in a production environment. Examples are also provided to relax some settings for test environments. When creating the cluster later in this guide, consider these example cluster manifests:
- cluster.yaml: Cluster settings for a production cluster running on bare metal. Requires at least three worker nodes.
- cluster-on-pvc.yaml: Cluster settings for a production cluster running in a dynamic cloud environment.
- cluster-test.yaml: Cluster settings for a test environment such as minikube.
See the Ceph examples for more details.
Deploy the Rook Operator
cd cluster/examples/kubernetes/ceph kubectl create -f crds.yaml -f common.yaml -f operator.yaml ## verify the rook-ceph-operator is in the `Running` state before proceeding kubectl -n rook-ceph get pod
You can also deploy the operator with the Rook Helm Chart.
Before you start the operator in production, there are some settings that you may want to consider:
- If you are using kubernetes v1.15 or older you need to create CRDs found here
/cluster/examples/kubernetes/ceph/pre-k8s-1.16/crd.yaml. The apiextension v1beta1 version of CustomResourceDefinition was deprecated in Kubernetes v1.16.
- Consider if you want to enable certain Rook features that are disabled by default. See the operator.yaml for these and other advanced settings.
- Device discovery: Rook will watch for new devices to configure if the
ROOK_ENABLE_DISCOVERY_DAEMONsetting is enabled, commonly used in bare metal clusters.
- Flex driver: The flex driver is deprecated in favor of the CSI driver, but can still be enabled with the
- Node affinity and tolerations: The CSI driver by default will run on any node in the cluster. To configure the CSI driver affinity, several settings are available.
- Device discovery: Rook will watch for new devices to configure if the
Create a Rook Ceph Cluster
Now that the Rook operator is running we can create the 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.
Create the cluster:
kubectl create -f cluster.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 configured.
If you did not modify the
cluster.yaml above, it is expected that one OSD will be created per node.
rook-ceph-agent (flex driver), and
rook-discover pods are also optional depending on your settings.
rook-ceph-osdpods are not created, please refer to the Ceph common issues for more details and potential solutions.
$ kubectl -n rook-ceph get pod NAME READY STATUS RESTARTS AGE csi-cephfsplugin-provisioner-d77bb49c6-n5tgs 5/5 Running 0 140s csi-cephfsplugin-provisioner-d77bb49c6-v9rvn 5/5 Running 0 140s csi-cephfsplugin-rthrp 3/3 Running 0 140s csi-rbdplugin-hbsm7 3/3 Running 0 140s csi-rbdplugin-provisioner-5b5cd64fd-nvk6c 6/6 Running 0 140s csi-rbdplugin-provisioner-5b5cd64fd-q7bxl 6/6 Running 0 140s rook-ceph-crashcollector-minikube-5b57b7c5d4-hfldl 1/1 Running 0 105s rook-ceph-mgr-a-64cd7cdf54-j8b5p 1/1 Running 0 77s rook-ceph-mon-a-694bb7987d-fp9w7 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-85f5b946bd-s8grz 1/1 Running 0 92m rook-ceph-osd-0-6bb747b6c5-lnvb6 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
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 Filesystem: Create a filesystem 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.