boot from image created with nova image-create from a volume backed instance is rejected

[Balazs Gibizer]

It is not possible to boot the image that was created with nova image-create from a volume backed instance.

Steps to reproduce:
stack@stack:~/devstack$ nova boot --flavor 100 --block-device source=image,id=70b5a8e8-846f-40dc-a52d-558d37dfc7f1,dest=volume,bootindex=0,size=1 volume-backed
+--------------------------------------+-------------------------------------------------+
| Property | Value |
+--------------------------------------+-------------------------------------------------+
| OS-DCF:diskConfig | MANUAL |
| OS-EXT-AZ:availability_zone | nova |
| OS-EXT-SRV-ATTR:host | - |
| OS-EXT-SRV-ATTR:hypervisor_hostname | - |
| OS-EXT-SRV-ATTR:instance_name | instance-00000017 |
| OS-EXT-STS:power_state | 0 |
| OS-EXT-STS:task_state | scheduling |
| OS-EXT-STS:vm_state | building |
| OS-SRV-USG:launched_at | - |
| OS-SRV-USG:terminated_at | - |
| accessIPv4 | |
| accessIPv6 | |
| adminPass | wvUa22QCTaoR |
| config_drive | |
| created | 2014-10-15T15:07:39Z |
| flavor | install-test (100) |
| hostId | |
| id | 9ad985f6-5e76-4545-9702-0b8a6058ef57 |
| image | Attempt to boot from volume - no image supplied |
| key_name | - |
| metadata | {} |
| name | volume-backed |
| os-extended-volumes:volumes_attached | [] |
| progress | 0 |
| security_groups | default |
| status | BUILD |
| tenant_id | 89dda4659c7e403392e9bcfc14ca6c80 |
| updated | 2014-10-15T15:07:39Z |
| user_id | 4c9283c1cbc54d688e2dda83fbc4aa11 |
+--------------------------------------+-------------------------------------------------+

stack@stack:~/devstack$ nova show 9ad985f6-5e76-4545-9702-0b8a6058ef57
+--------------------------------------+----------------------------------------------------------+
| Property | Value |
+--------------------------------------+----------------------------------------------------------+
| OS-DCF:diskConfig | MANUAL |
| OS-EXT-AZ:availability_zone | nova |
| OS-EXT-SRV-ATTR:host | stack |
| OS-EXT-SRV-ATTR:hypervisor_hostname | stack |
| OS-EXT-SRV-ATTR:instance_name | instance-00000017 |
| OS-EXT-STS:power_state | 1 |
| OS-EXT-STS:task_state | - |
| OS-EXT-STS:vm_state | active |
| OS-SRV-USG:launched_at | 2014-10-15T15:07:47.000000 |
| OS-SRV-USG:terminated_at | - |
| accessIPv4 | |
| accessIPv6 | |
| config_drive | |
| created | 2014-10-15T15:07:39Z |
| flavor | install-test (100) |
| hostId | 337fdcb2bd1ee3ad5bbe5e498310984745f473c82ef41b7276d1b449 |
| id | 9ad985f6-5e76-4545-9702-0b8a6058ef57 |
| image | Attempt to boot from volume - no image supplied |
| key_name | - |
| metadata | {} |
| name | volume-backed |
| os-extended-volumes:volumes_attached | [{"id": "fdcc1414-a42e-42f7-803e-d40f8b872787"}] |
| private network | 10.0.0.2 |
| progress | 0 |
| security_groups | default |
| status | ACTIVE |
| tenant_id | 89dda4659c7e403392e9bcfc14ca6c80 |
| updated | 2014-10-15T15:07:47Z |
| user_id | 4c9283c1cbc54d688e2dda83fbc4aa11 |
+--------------------------------------+----------------------------------------------------------+
stack@stack:~/devstack$ nova image-create 9ad985f6-5e76-4545-9702-0b8a6058ef57 image-from-volume-backed
stack@stack:~/devstack$ nova image-show image-from-volume-backed
+-------------------------------+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| Property | Value |
+-------------------------------+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| OS-EXT-IMG-SIZE:size | 0 |
| created | 2014-10-15T15:10:40Z |
| id | c0283b1b-e567-48ce-b784-0ff1ce8245bb |
| metadata bdm_v2 | True |
| metadata block_device_mapping | [{"guest_format": null, "boot_index": 0, "no_device": null, "image_id": null, "snapshot_id": "ed729800-36ab-4ba1-89c2-36f99bd398a9", "disk_bus": "virtio", "volume_size": null, "source_type": "snapshot", "device_type": "disk", "volume_id": null, "destination_type": "volume", "delete_on_termination": null}] |
| metadata checksum | 4eada48c2843d2a262c814ddc92ecf2c |
| metadata container_format | ami |
| metadata disk_format | ami |
| metadata image_id | 70b5a8e8-846f-40dc-a52d-558d37dfc7f1 |
| metadata image_name | cirros-0.3.2-x86_64-uec |
| metadata kernel_id | 3d8e1ae1-7e24-45d8-9064-adfcf18d1b80 |
| metadata min_disk | 0 |
| metadata min_ram | 0 |
| metadata ramdisk_id | 5634fe26-f909-4c88-a455-e6e44fa8ee56 |
| metadata root_device_name | /dev/vda |
| metadata size | 25165824 |
| minDisk | 0 |
| minRam | 0 |
| name | image-from-volume-backed |
| progress | 100 |
| status | ACTIVE |
| updated | 2014-10-15T15:10:40Z |
+-------------------------------+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+

stack@stack:~/devstack$ nova boot --flavor 100 --block-device source=image,id=c0283b1b-e567-48ce-b784-0ff1ce8245bb,dest=volume,bootindex=0,size=1 volume-backed-from-snap-image
ERROR (BadRequest): Block Device Mapping is Invalid: Boot sequence for the instance and image/block device mapping combination is not valid. (HTTP 400) (Request-ID: req-87ae0d82-65dc-4b7b-ac99-88f70b7fe32c)

It seems that it is only a validation problem on API level as the same image can be booted with --image parameter.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/128891

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/128891
Committed: https://git.openstack.org/cgit/openstack/nova/commit/?id=48fca2fa32bf9f8cf2bba035fc3ad6fd9170e6f4
Submitter: Jenkins
Branch: master

commit 48fca2fa32bf9f8cf2bba035fc3ad6fd9170e6f4
Author: Balazs Gibizer <email address hidden>
Date: Wed Oct 15 16:58:55 2014 +0200

    Fix bdm transformation for volume backed servers

    When volume backed server is snapshoted with nova image-create
    then the image is created with a proper bdm. However when this
    image is booted with image->volume bdm the two bdms are not
    merged properly and the server cannot be booted as it gets two
    boot_index = 0 device

    This patch solves the issue by removing the unnecessary device
    from the mapping.

    Closes-bug: #1381598

    Change-Id: I170e80d35fe8a8d906370a507148351926763a13