The 'force' parameter of os-brick's disconnect_volume() method allows
callers to ignore flushing errors and ensure that devices are being
removed from the host.
We should use force=True when we are going to delete an instance to
avoid leaving leftover devices connected to the compute host which
could then potentially be reused to map to volumes to an instance that
should not have access to those volumes.
We can use force=True even when disconnecting a volume that will not be
deleted on termination because os-brick will always attempt to flush
and disconnect gracefully before forcefully removing devices.
Closes-Bug: #2004555
Change-Id: I3629b84d3255a8fe9d8a7cea8c6131d7c40899e8
(cherry picked from commit db455548a1)
5.3 KiB
Use snapshots to migrate instances
This guide can be used to migrate an instance between different clouds.
To use snapshots to migrate instances from OpenStack projects to clouds, complete these steps.
In the source project:
Create_a_snapshot_of_the_instanceDownload_the_snapshot_as_an_image
In the destination project:
Import_the_snapshot_to_the_new_environmentBoot_a_new_instance_from_the_snapshot
Note
Some cloud providers allow only administrators to perform this task.
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 the instance name:
$ openstack server list +--------------------------------------+------------+--------+------------------+--------------------+-------------------------+ | ID | Name | Status | Networks | Image | Flavor | +--------------------------------------+------------+--------+------------------+--------------------+-------------------------+ | d0d1b7d9-a6a5-41d3-96ab-07975aadd7fb | myInstance | ACTIVE | private=10.0.0.3 | ubuntu-16.04-amd64 | general.micro.tmp.linux | +--------------------------------------+------------+--------+------------------+--------------------+-------------------------+Use the
openstack server stopcommand to shut down the instance:$ openstack server stop myInstanceUse the
openstack server listcommand to confirm that the instance shows aSHUTOFFstatus:$ openstack server list +--------------------------------------+------------+---------+------------------+--------------------+-------------------------+ | ID | Name | Status | Networks | Image | Flavor | +--------------------------------------+------------+---------+------------------+--------------------+-------------------------+ | d0d1b7d9-a6a5-41d3-96ab-07975aadd7fb | myInstance | SHUTOFF | private=10.0.0.3 | ubuntu-16.04-amd64 | general.micro.tmp.linux | +--------------------------------------+------------+---------+------------------+--------------------+-------------------------+Use the
openstack server image createcommand to take a snapshot:$ openstack server image create --name myInstanceSnapshot myInstanceIf snapshot operations routinely fail because the user token times out while uploading a large disk image, consider configuring nova to use
service user tokens <service_user_token>.Use the
openstack image listcommand to check the status until the status isACTIVE:$ openstack image list +--------------------------------------+---------------------------+--------+ | ID | Name | Status | +--------------------------------------+---------------------------+--------+ | ab567a44-b670-4d22-8ead-80050dfcd280 | myInstanceSnapshot | active | +--------------------------------------+---------------------------+--------+
Download the snapshot as an image
Get the image ID:
$ openstack image list +--------------------------------------+---------------------------+--------+ | ID | Name | Status | +--------------------------------------+---------------------------+--------+ | ab567a44-b670-4d22-8ead-80050dfcd280 | myInstanceSnapshot | active | +--------------------------------------+---------------------------+--------+Download the snapshot by using the image ID that was returned in the previous step:
$ openstack image save --file snapshot.raw ab567a44-b670-4d22-8ead-80050dfcd280Note
The
openstack image savecommand requires the image ID and cannot use the image name. Check 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 direct upload to a machine (
scp).
Import the snapshot to the new environment
In the new project or cloud environment, import the snapshot:
$ openstack image create --container-format bare --disk-format qcow2 \
--file snapshot.raw myInstanceSnapshot
Boot a new instance from the snapshot
In the new project or cloud environment, use the snapshot to create the new instance:
$ openstack server create --flavor m1.tiny --image myInstanceSnapshot myNewInstance