Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Documentation for CSIPersistentVolume #6504

Merged
merged 1 commit into from
Dec 1, 2017
Merged

Documentation for CSIPersistentVolume #6504

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
33 changes: 33 additions & 0 deletions docs/concepts/storage/volumes.md
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -69,6 +69,7 @@ Kubernetes supports several types of Volumes:
* `azureDisk`
* `azureFile`
* `cephfs`
* `csi`
* `downwardAPI`
* `emptyDir`
* `fc` (fibre channel)
Expand Down Expand Up @@ -170,6 +171,38 @@ writers simultaneously.

See the [CephFS example](https://github.com/kubernetes/examples/tree/{{page.githubbranch}}/staging/volumes/cephfs/) for more details.

### csi

CSI stands for [Container Storage Interface](https://github.com/container-storage-interface/spec/blob/master/spec.md),
a specification attempting to establish an industry standard interface that
Container Orchestration Systems (COs) can use to expose arbitrary storage systems
to their container workloads.
For more information about the details, please check the
[design proposal](https://github.com/kubernetes/community/blob/master/contributors/design-proposals/storage/container-storage-interface.md).

<!-- TODO: add link to the kubernetes extension section -->
The `csi` volume type is an in-tree CSI volume plugin for Pods to interact
with external CSI volume drivers running on the same node.
After having deployed a CSI compatible volume driver, users can use `csi` as the
volume type to mount the storage provided by the driver.

CSI persistent volume support is introduced in Kubernetes v1.9 as an alpha feature
which has to be explicitly enabled by the cluster administrator. In other words,
the cluster administrator needs to add "`CSIPersistentVolume=true`" to the
"`--feature-gates=`" flag for the apiserver, the controller-manager and the kubelet
components.

A CSI persistent volume has the following fields for users to specify:

- `driver`: A string value that specifies the name of the volume driver to use.
It has to be less than 63 characters and starts with a character. The driver
name can have '`.`', '`-`', '`_`' or digits in it.
- `volumeHandle`: A string value that uniquely identify the volume name returned
from the CSI volume plugin's `CreateVolume` call. The volume handle is then
used in all subsequent calls to the the volume driver for referencing the volume.
- `readOnly`: An optional boolean value indicating whether the volume is to be
published as read only. Default is false.

### downwardAPI

A `downwardAPI` volume is used to make downward API data available to applications.
Expand Down