cri-o/vendor/k8s.io/kubernetes/examples/volumes/rbd/README.md

60 lines
2.6 KiB
Markdown
Raw Normal View History

# How to Use it?
Install Ceph on the Kubernetes host. For example, on Fedora 21
# yum -y install ceph-common
If you don't have a Ceph cluster, you can set up a [containerized Ceph cluster](https://github.com/ceph/ceph-docker)
Then get the keyring from the Ceph cluster and copy it to */etc/ceph/keyring*.
Once you have installed Ceph and new Kubernetes, you can create a pod based on my examples [rbd.json](rbd.json) [rbd-with-secret.json](rbd-with-secret.json). In the pod JSON, you need to provide the following information.
- *monitors*: Ceph monitors.
- *pool*: The name of the RADOS pool, if not provided, default *rbd* pool is used.
- *image*: The image name that rbd has created.
- *user*: The RADOS user name. If not provided, default *admin* is used.
- *keyring*: The path to the keyring file. If not provided, default */etc/ceph/keyring* is used.
- *secretName*: The name of the authentication secrets. If provided, *secretName* overrides *keyring*. Note, see below about how to create a secret.
- *fsType*: The filesystem type (ext4, xfs, etc) that formatted on the device.
- *readOnly*: Whether the filesystem is used as readOnly.
# Use Ceph Authentication Secret
If Ceph authentication secret is provided, the secret should be first be *base64 encoded*, then encoded string is placed in a secret yaml. For example, getting Ceph user `kube`'s base64 encoded secret can use the following command:
```console
# grep key /etc/ceph/ceph.client.kube.keyring |awk '{printf "%s", $NF}'|base64
QVFBTWdYaFZ3QkNlRGhBQTlubFBhRnlmVVNhdEdENGRyRldEdlE9PQ==
```
An example yaml is provided [here](secret/ceph-secret.yaml). Then post the secret through ```kubectl``` in the following command.
```console
# kubectl create -f examples/volumes/rbd/secret/ceph-secret.yaml
```
# Get started
Here are my commands:
```console
# kubectl create -f examples/volumes/rbd/rbd.json
# kubectl get pods
```
On the Kubernetes host, I got these in mount output
```console
#mount |grep kub
/dev/rbd0 on /var/lib/kubelet/plugins/kubernetes.io/rbd/rbd/kube-image-foo type ext4 (ro,relatime,stripe=4096,data=ordered)
/dev/rbd0 on /var/lib/kubelet/pods/ec2166b4-de07-11e4-aaf5-d4bed9b39058/volumes/kubernetes.io~rbd/rbdpd type ext4 (ro,relatime,stripe=4096,data=ordered)
```
If you ssh to that machine, you can run `docker ps` to see the actual pod and `docker inspect` to see the volumes used by the container.
<!-- BEGIN MUNGE: GENERATED_ANALYTICS -->
[![Analytics](https://kubernetes-site.appspot.com/UA-36037335-10/GitHub/examples/volumes/rbd/README.md?pixel)]()
<!-- END MUNGE: GENERATED_ANALYTICS -->