Migrating images

The image migration handler is an essential part of the openstack-migrate tool since it’s also used to transfer Nova instance and Cinder volume data.

Transferred images do not get written to disk. Instead, the data is retrieved and uploaded in chunks that are kept entirely in memory. The same applies to Barbican secrets.

The chunk size can be configured through the image_transfer_chunk_size setting, defaulting to 32MB.

Example

The following example migrates an image and removes it from the source cloud:

  openstack-migrate start \
    --include-dependencies \
    --resource-type=image \
    --cleanup-source \
    08d44d29-94fb-4ccd-8828-082471648dce

2025-12-18 09:16:34,568 INFO Initiating image migration, resource id: 08d44d29-94fb-4ccd-8828-082471648dce
2025-12-18 09:16:35,378 INFO Migrating associated project resource: a37bddfe63dc4c19bf981ee971c1ef5d
2025-12-18 09:16:35,379 INFO Initiating project migration, resource id: a37bddfe63dc4c19bf981ee971c1ef5d
2025-12-18 09:16:35,957 INFO Migrating associated domain resource: 38da677b7dd944f8bce50bba4342bda6
2025-12-18 09:16:35,958 INFO Initiating domain migration, resource id: 38da677b7dd944f8bce50bba4342bda6
2025-12-18 09:16:37,456 WARNING Domain already exists: 6f05f02ce89b4976bb6f06bce3d2a40a admin_domain
2025-12-18 09:16:37,464 INFO Successfully migrated domain resource, destination id: 6f05f02ce89b4976bb6f06bce3d2a40a
2025-12-18 09:16:39,413 WARNING Project already exists: ba010cba17534749b67dd8d5efc95f84 test-3514969242-owner
2025-12-18 09:16:39,425 INFO Successfully migrated project resource, destination id: ba010cba17534749b67dd8d5efc95f84
2025-12-18 09:16:43,216 INFO Successfully migrated image resource, destination id: c0cf38bd-0887-4962-86f9-8d502659e666
2025-12-18 09:16:43,225 INFO Migration succeeded, cleaning up source image: 08d44d29-94fb-4ccd-8828-082471648dce