10. Use snapshots to migrate instances

To use snapshots to migrate instances from OpenStack projects to clouds, complete these steps.

In the source project, perform the following steps:
1. Create a snapshot of the instance.
2. Download the snapshot as an image.
In the destination project, perform the following steps:
1. Import the snapshot to the new environment.
2. Boot a new instance from the snapshot.

Note

Some cloud providers allow only administrators to perform this task.

10.1. Create a snapshot of the instance

Shut down the source VM before you take the snapshot to ensure that all data is flushed to disk. If necessary, list the instances to view get the instance name.

$ nova list
+--------------------------------------+------------+--------+------------------------------+
| ID                                   | Name       | Status | Networks                     |
+--------------------------------------+------------+--------+------------------------------+
| c41f3074-c82a-4837-8673-fa7e9fea7e11 | myInstance | ACTIVE | private=10.0.0.3             |
+--------------------------------------+------------+--------+------------------------------+

$ nova stop example

Use the nova list command to confirm that the instance shows a SHUTOFF status.

$ nova list
+--------------------------------------+------------+---------+------------------------------+
| ID                                   | Name       | Status  | Networks                     |
+--------------------------------------+------------+---------+------------------------------+
| c41f3074-c82a-4837-8673-fa7e9fea7e11 | myInstance | SHUTOFF | private=10.0.0.3             |
+--------------------------------------+------------+---------+------------------------------+

Use the nova image-create command to take a snapshot. Use the nova image-list command to check the status until the status is ACTIVE:

$ nova image-create --poll myInstance myInstanceSnapshot
Instance snapshotting... 50% complete

$ nova image-list
+--------------------------------------+---------------------------------+--------+--------+
| ID                                   | Name                            | Status | Server |
+--------------------------------------+---------------------------------+--------+--------+
| 657ebb01-6fae-47dc-986a-e49c4dd8c433 | cirros-0.3.2-x86_64-uec         | ACTIVE |        |
| 72074c6d-bf52-4a56-a61c-02a17bf3819b | cirros-0.3.2-x86_64-uec-kernel  | ACTIVE |        |
| 3c5e5f06-637b-413e-90f6-ca7ed015ec9e | cirros-0.3.2-x86_64-uec-ramdisk | ACTIVE |        |
| f30b204e-1ce6-40e7-b8d9-b353d4d84e7d | myInstanceSnapshot              | ACTIVE |        |
+--------------------------------------+---------------------------------+--------+--------+

10.2. Download the snapshot as an image

Get the image ID:

$ nova image-list
+--------------------------------------+-------------------+--------+--------------------------------------+
| ID                                   | Name              | Status | Server                               |
+--------------------------------------+-------------------+--------+--------------------------------------+
| f30b204e-1ce6-40e7-b8d9-b353d4d84e7d | myInstanceSnapshot| ACTIVE | c41f3074-c82a-4837-8673-fa7e9fea7e11 |
+--------------------------------------+-------------------+--------+--------------------------------------+

Download the snapshot by using the image ID that was returned in the previous step:
```
$ glance image-download --file snapshot.raw f30b204e-1ce6-40e7-b8d9-b353d4d84e7d
```
Note
The glance image-download command requires the image ID and cannot use the image name.
Ensure there is sufficient space on the destination file system for the image file.
Make the image available to the new environment, either through HTTP or with direct upload to a machine (scp).

10.3. Import the snapshot to new environment

In the new project or cloud environment, import the snapshot:

$ glance image-create --copy-from IMAGE_URL --name myInstanceSnapshot

10.4. Boot a new instance from the snapshot

In the new project or cloud environment, use the snapshot to create the new instance:

$ nova boot --flavor m1.tiny --image myInstanceSnapshot \ 
--nic net-id=3d706957-7696-4aa8-973f-b80892ff9a95 myNewInstance