deb-murano/doc/source/appdev-guide/cinder_volume_supporting.rst

Cinder volume support

Cinder volume is a block storage service for OpenStack, which represents a detachable device, similar to a USB hard drive. You can attach a volume to only one instance. In murano, it is possible to work with Cinder volumes in several ways:

• Attaching Cinder volumes to murano instance
• Booting from Cinder volume

Below both ways are considered with ApacheHttpServer application as an example.

For more information about Cinder volumes, see Manage Cinder volumes.

Attaching Cinder volumes

Several volumes can be attached to the murano instance. Consider an example that shows how to attach a created volume to the instance (next, in the Booting from Cinder volume section, we are going to boot from a volume created by us).

Example

1. In the Openstack dashboard, go to Volumes to create a volume.
2. Modify the ui.yaml file:

....

Application:
  ....
  instance:
    ....
    volumes:
      $.volumeConfiguration.volumePath:
        ?:
          type: io.murano.resources.ExistingCinderVolume
        openstackId: $.volumeConfiguration.volumeID

 ....

An existing Cinder volume can be initialized with its openstackId and can be attached with its volumePath. These parameters come here from modified Forms section of the ui.yaml file:

....

Forms:
  - appConfiguration:
      ....
  - instanceConfiguration:
      ....
  - volumeConfiguration:
      fields:
        - name: volumeID
          type: string
          label: Existing volume ID
          description: Put in existing volume openstackID
          required: true
        - name: volumePath
          type: string
          label: Path
          description: Put in volume path to be mounted
          required: true

Therefore, create a ZIP archive of the built package and upload it to murano. Attach created application to the environment. Enter its openstackId (which can be found in Openstack dashboard) and path for mounting. For example, you can fill the latter with /dev/vdb value.

After the application is deployed, verify that the volume is attached to the instance in the OpenStack dashboard Volumes tab. Alternatively, see the topology of the Heat Stack.

Booting from Cinder volume

You can create a volume from an existing image. The example below shows how to create a volume from an image and use the volume to boot an instance.

Example

It is possible to create a volume through the Heat template, instead of the OpenStack dashboard. For this, modify the ui.yaml file:

....

Templates:
  customJoinNet:
    ....
  bootVolumes:
    - volume:
        ?:
          type: io.murano.resources.CinderVolume
        size: $.instanceConfiguration.volSize
        sourceImage: $.instanceConfiguration.osImage
      bootIndex: 0
      deviceName: vda
      deviceType: disk
....

Application:
  ....
  instance:
    ....
    blockDevices: $bootVolumes

....

The example above shows that the Templates section now has a bootVolumes field, which is stored in the changed Application section. Pay attention that image property should be deleted from Application to avoid defining both image and volume to boot. The size and sourceImage properties come in Templates from the changed Forms section of the ui.yaml file:

....

Forms:
  - appConfiguration:
      ....

  - instanceConfiguration:
      fields:
        ....
        - name: volSize
          type: integer
          label: Size of volume
          required: true
          description: >-
            Specify volume size which is going to be created from image
        ....

After sending this package to murano you can boot your instance from the volume by chosen image.