.. _compute_inst_snap_create_card:

Instance: snapshot create
=========================

The creation of a snapshot image from an existing VM hosted on OpenStack will 
differ depending on whether the VM is ephemeral or instantiated from a bootable drive, namely bootable VM (see :ref:`cloud/os_overview/os_components/compute:instances`).

Preliminary steps
^^^^^^^^^^^^^^^^^
Independently, from the type of VM, it is safer to create the snapshot, after the VM has been shut down. 
In the :ref:`cloud/os_overview/management_tools/dashboard:horizon dashboard`:

- Shutdown the VM
- Detach any secondary volume attached on the VM (remember the volume */dev/vda* is the bootable volume from which the VM is loaded).

Ephemeral VM
^^^^^^^^^^^^^

If the VM is loaded from an image, there is no bootable volume */dev/vda*.

.. tab-set::

   .. tab-item:: Horizon dashboard

      - In the Horizon Dashboard, go to *Compute → Instances*
      - Click on *"Create snapshot"* action for the instance to snapshot 
      
      .. image:: /cloud/_img/op_snap_create_1.jpg

      - From the pop-up dialog, give a unique *“Snapshot Name”* for the image snapshot file, then click on the *“Create Snapshot”*.

      .. image:: /cloud/_img/op_snap_create_2.jpg

      - The procedure will bring you to the *"Compute → Images"* section, where the snapshot image will appear after the generation process indicated by the transition of the image *“Status”* from *“Queued”* to *“Active”*, passing from *“Saving”*. 
      - At the end the snapshot should appear with size different from zero.

      .. image:: /cloud/_img/op_snap_create_3.jpg

   .. tab-item:: Command Line Interface

      - Configure your CLI following the steps in :ref:`cloud/os_overview/management_tools/command_line:command line interface`
      - Obtain the complete tabular list of all the servers available on the tenant 

       .. code-block:: bash
        
                openstack server list 
                +----------------+------------------+--------+-----+------------------+ 
                | ID             | Name             | Status | ... | Flavor           | 
                +----------------+------------------+--------+-----+------------------+ 
                | <Server-ID-01> | <Server-Name-01> | ACTIVE |     | <Flavor-Name-01> | 
                | <Server-ID-02> | <Server-Name-02> | ACTIVE |     | <Flavor-Name-02> | 
                | <Server-ID-03> | <Server-Name-03> | ACTIVE |     | <Flavor-Name-03> | 
                ... 
                | <Server-ID>    | <Server-Name>    | ACTIVE |     | <Flavor-Name>    | 
                +----------------+------------------+--------+-----+------------------+

      - Use the ID corresponding to the server name from which is desired to generate a snapshot image to run the command   

       .. code-block:: bash
        
                openstack server image create --name <snapshot-name> --wait <Server-ID>     

      - Even if the CLI does not show a progress bar for the snapshotting procedure, the shell will hang until the snapshot image *“Status”* will become *“Active”*. 
      - At the completion of the creation, you can check if the snapshot has been correctly created and in active state with the command

       .. code-block:: bash
        
                openstack image list --name <snapshot-name>
                +---------------+------------------+--------+
                | ID            | Name             | Status |
                +---------------+------------------+--------+
                | <Image-ID>    | <snapshot-name>  | active |
                +---------------+------------------+--------+

Bootable VM
^^^^^^^^^^^^^
If the VM is loaded from a bootable volume, there is a volume attached as */dev/vda*.

.. important::
   For bootable VM, the snapshotting procedure can be done only if the **bootable volume is not set to be deleted** once the attached VM will be deleted. 

Before starting the creation of the VM snapshot, 

- save the ID of the bootable volume from which your VM has been created (<volume-ID>)
- delete the VM instance to snapshot following the instructions in :ref:`cloud/operative/compute_ops/instance_deletion:instance: delete`.


.. tab-set::

   .. tab-item:: Horizon dashboard

      - Navigate to *"Volumes → Volumes"*
      - On the row corresponding to the volume attached to the previously deleted instance, click on the action *“Upload to Image”*. 

         .. image:: /cloud/_img/op_snap_create_5.jpg

      - From the pop-up dialog, give a unique *“Snapshot Name”* for the image snapshot file, then click on *“Upload”*. 

         .. image:: /cloud/_img/op_snap_create_6.jpg

      - The procedure will close the pop-up window and the status of the volume will change to *“uploading”*.
        
         .. image:: /cloud/_img/op_snap_create_7.jpg

      - Once the status of the volume will become once again *“Available”*, a snapshot image of the volume will appear in the *“Compute → Images”* section with a size different from zero.  

   .. tab-item:: Command Line Interface

      - Configure your CLI following the steps in :ref:`cloud/os_overview/management_tools/command_line:command line interface`
      - Use the bootable <volume-ID>, saved before, to upload a snapshot image 

        .. code-block:: bash
        
               openstack image create --volume <volume-ID> <snapshot-name>
               +---------------------+--------------------------------------+
               | Field               | Value                                |
               +---------------------+--------------------------------------+
               | container_format    | bare                                 |
               | disk_format         | raw                                  |
               | display_description |                                      |
               | id                  | <Volume-ID>                          |
               | image_id            | <Snapshot-Image-ID>                  |
               | image_name          | <snapshot-name>                      |
               | protected           | False                                |
               | size                | <Volume-size>                        |
               | status              | uploading                            |
               | updated_at          | <Creation-date>                      |
               | visibility          | shared                               |
               | volume_type         | __DEFAULT__                          |
               +---------------------+--------------------------------------+

      - The creation will be completed, once the status of the image will become *“Available”*, you can check this with 
  
       .. code-block:: bash
        
                openstack image list --name <snapshot-name>
                +---------------+------------------+--------+
                | ID            | Name             | Status |
                +---------------+------------------+--------+
                | <Image-ID>    | <snapshot-name>  | active |
                +---------------+------------------+--------+