resume guests on libvirt host reboot fails for instances created from multi-part image

[Alex Ermolov]

This is backport for upstream fix for: https://bugs.launchpad.net/nova/+bug/1195884

Original description:
=====================

If an instance is created from a multi-part image (i.e. separate kernel and ramdisk files) , and resume_guests_state_on_host_boot=True the resulting _hard_reboot will fail and put the instance into an error state.

This is because the code in _hard_reboot that checks the image files, _create_images_and_backing() always tries to reload these from Glance.

In a normal reboot this results in an unnecessary image download from Glance.

In the case of reboot following a host boot the download fails because the context at this point does not have credentials to be able to access Glance.

Possible fix is to:
- Check files exist rather than always trying to download them
- Provide in conf credentials of a user that has read access to all images in Glance than can be used in this context

[Fuel Devops McRobotson (fuel-devops-robot)]

Fix proposed to branch: openstack-ci/fuel-6.1/2014.2
Change author: Alex Ermolov <email address hidden>
Review: https://review.fuel-infra.org/7667

[Fuel Devops McRobotson (fuel-devops-robot)]

Fix proposed to branch: openstack-ci/fuel-6.0-updates/2014.2
Change author: Alex Ermolov <email address hidden>
Review: https://review.fuel-infra.org/7716

[Fuel Devops McRobotson (fuel-devops-robot)]

Reviewed: https://review.fuel-infra.org/7716
Submitter: Vitaly Sedelnik <email address hidden>
Branch: openstack-ci/fuel-6.0-updates/2014.2

Commit: 988c7be9958abd1b88f282ed768f513038804450
Author: Alex Ermolov <email address hidden>
Date: Wed Jun 10 15:09:32 2015

libvirt: Handle empty context on _hard_reboot

When _hard_reboot runs for resume_guest_state_on_host_boot, we don't
have a valid context. This checks if the context is valid before
attempting to repopulate base images.

This is a bit of a hack, as it assumes that the base images already
exist on the system, and will fail if they don't. However, it reduces
the number of failures (without this, every downed guest is guaranteed
to error when coming back up for resume_guest_state_on_host_boot).

Closes-Bug: 1462991
Change-Id: Ibac52f5d1b4e5ab2adb0a561659e6df8c7c1f40f

[Fuel Devops McRobotson (fuel-devops-robot)]

Fix proposed to branch: master
Change author: Denis V. Meltsaykin <email address hidden>
Review: https://review.fuel-infra.org/7985

[Fuel Devops McRobotson (fuel-devops-robot)]

Change abandoned by Denis V. Meltsaykin <email address hidden> on branch: master
Review: https://review.fuel-infra.org/7985

[Fuel Devops McRobotson (fuel-devops-robot)]

Fix proposed to branch: stable/6.1
Change author: Denis V. Meltsaykin <email address hidden>
Review: https://review.fuel-infra.org/8628

[Fuel Devops McRobotson (fuel-devops-robot)]

Reviewed: https://review.fuel-infra.org/8628
Submitter: Alex Khivin <email address hidden>
Branch: stable/6.1

Commit: f24dcd76db197c0d62f8a585f70e813446eba25b
Author: Denis V. Meltsaykin <email address hidden>
Date: Wed Jul 1 14:11:16 2015

libvirt: Handle empty context on _hard_reboot

When _hard_reboot runs for resume_guest_state_on_host_boot,
we don't have a valid context. This checks if the context
is valid before attempting to repopulate base images.
This is a bit of a hack, as it assumes that the base images
already exist on the system, and will fail if they don't.
However, it reduces the number of failures (without this,
every downed guest is guaranteed to error when coming back
up for resume_guest_state_on_host_boot).

Change-Id: I82db6963f9cbfa2ce103e11754cb53a5a7bd2aa1
Closes-Bug: 1462991

[Fuel Devops McRobotson (fuel-devops-robot)]

Fix proposed to branch: stable/6.1
Change author: Denis V. Meltsaykin <email address hidden>
Review: https://review.fuel-infra.org/8967

[Fuel Devops McRobotson (fuel-devops-robot)]

Reviewed: https://review.fuel-infra.org/8967
Submitter: Alex Khivin <email address hidden>
Branch: stable/6.1

Commit: 42bb875b43e65996598898015c7515e3ff96388a
Author: Denis V. Meltsaykin <email address hidden>
Date: Thu Jul 2 13:44:59 2015

libvirt: Handle empty context on _hard_reboot

When _hard_reboot runs for resume_guest_state_on_host_boot,
we don't have a valid context. This checks if the context is
valid before attempting to repopulate base images.
This is a bit of a hack, as it assumes that the base images
already exist on the system, and will fail if they don't.
However, it reduces the number of failures (without this,
every downed guest is guaranteed to error when coming back up for
resume_guest_state_on_host_boot).

Change-Id: Idcc973b049b78e1ac4f4dd3177fee899340b86f9
Partial-Bug: 1462991

[Fuel Devops McRobotson (fuel-devops-robot)]

Related fix proposed to branch: stable/6.1
Change author: Denis V. Meltsaykin <email address hidden>
Review: https://review.fuel-infra.org/8970

[Fuel Devops McRobotson (fuel-devops-robot)]

Reviewed: https://review.fuel-infra.org/8970
Submitter: Alex Khivin <email address hidden>
Branch: stable/6.1

Commit: 26520c6439350251826468997f31f10b151e0c46
Author: Denis V. Meltsaykin <email address hidden>
Date: Thu Jul 2 14:17:08 2015

Fix for 1462991

Fixing erratum to tests run better

Change-Id: Ibb3ce73283e6cb6d05d22242a1adac538fbda89c
Related-Bug: 1462991

[Fuel Devops McRobotson (fuel-devops-robot)]

Reviewed: https://review.fuel-infra.org/9116
Submitter: Alexey Shtokolov <email address hidden>
Branch: stable/6.1

Commit: 480947d7dedd2d9f6362eb2c1a7ec540d0ffde27
Author: Vadim Rovachev <email address hidden>
Date: Tue Jul 7 15:27:24 2015

Add workaround for centos distro for glance part images bug

Added one more time reboot for computes for reproduce bug
with error instance state and part images.

Closes-Bug: #1462991

Change-Id: If159fbf9889a34ce771c66f3a520ceeb627c989f

[Fuel Devops McRobotson (fuel-devops-robot)]

Reviewed: https://review.fuel-infra.org/7667
Submitter: Vitaly Sedelnik <email address hidden>
Branch: openstack-ci/fuel-6.1/2014.2

Commit: 426d17259ad75c4e9180cb7452afa45062b47d01
Author: Alex Ermolov <email address hidden>
Date: Tue Jun 9 16:28:40 2015

libvirt: Handle empty context on _hard_reboot

When _hard_reboot runs for resume_guest_state_on_host_boot, we don't
have a valid context. This checks if the context is valid before
attempting to repopulate base images.

This is a bit of a hack, as it assumes that the base images already
exist on the system, and will fail if they don't. However, it reduces
the number of failures (without this, every downed guest is guaranteed
to error when coming back up for resume_guest_state_on_host_boot).

Closes-Bug: 1462991
Change-Id: Ibac52f5d1b4e5ab2adb0a561659e6df8c7c1f40f

[Fuel Devops McRobotson (fuel-devops-robot)]

Reviewed: https://review.fuel-infra.org/9161
Submitter: Vitaly Sedelnik <email address hidden>
Branch: stable/6.1

Commit: 5c4de400d8281940905a2a6bcb583ae5b987322c
Author: Denis V. Meltsaykin <email address hidden>
Date: Wed Jul 8 17:09:18 2015

Change in 1462991's description

Related-Bug: #1462991

Change-Id: Ib7e93e43b75ec589db162f8d74665b96b6daa79a

[Fuel Devops McRobotson (fuel-devops-robot)]

Related fix proposed to branch: stable/6.1
Change author: Denis V. Meltsaykin <email address hidden>
Review: https://review.fuel-infra.org/9217

[Fuel Devops McRobotson (fuel-devops-robot)]

Reviewed: https://review.fuel-infra.org/9217
Submitter: Vitaly Sedelnik <email address hidden>
Branch: stable/6.1

Commit: 478bfc270fda2bc7e870c311bec645885659b828
Author: Denis V. Meltsaykin <email address hidden>
Date: Fri Jul 10 10:45:11 2015

Small description/title changes

Change-Id: I13cbc5a659ece19791ce6c7ed1c1823ebcaf2fb5
Related-Bug: #1462991

[Fuel Devops McRobotson (fuel-devops-robot)]

Change abandoned by Alex Ermolov <email address hidden> on branch: openstack-ci/fuel-5.1.1-updates/2014.1.1
Review: https://review.fuel-infra.org/8901

[Fuel Devops McRobotson (fuel-devops-robot)]

Change restored by Alex Ermolov <email address hidden> on branch: openstack-ci/fuel-5.1.1-updates/2014.1.1
Review: https://review.fuel-infra.org/8901

[Fuel Devops McRobotson (fuel-devops-robot)]

Fix proposed to branch: openstack-ci/fuel-5.1.1-updates/2014.1.1
Change author: Alex Ermolov <email address hidden>
Review: https://review.fuel-infra.org/9383

[Fuel Devops McRobotson (fuel-devops-robot)]

Change abandoned by Alex Ermolov <email address hidden> on branch: openstack-ci/fuel-5.1.1-updates/2014.1.1
Review: https://review.fuel-infra.org/8901

[Fuel Devops McRobotson (fuel-devops-robot)]

Fix proposed to branch: openstack-ci/fuel-5.1-updates/2014.1.1
Change author: Alex Ermolov <email address hidden>
Review: https://review.fuel-infra.org/9393

[Fuel Devops McRobotson (fuel-devops-robot)]

Reviewed: https://review.fuel-infra.org/9393
Submitter: Vitaly Sedelnik <email address hidden>
Branch: openstack-ci/fuel-5.1-updates/2014.1.1

Commit: 1dec25b1fec7ddb29d08e390999dbfbbcdf70863
Author: Alex Ermolov <email address hidden>
Date: Wed Jul 15 16:09:52 2015

libvirt: Handle empty context on _hard_reboot

When _hard_reboot runs for resume_guest_state_on_host_boot, we don't
have a valid context. This checks if the context is valid before
attempting to repopulate base images.

This is a bit of a hack, as it assumes that the base images already
exist on the system, and will fail if they don't. However, it reduces
the number of failures (without this, every downed guest is guaranteed
to error when coming back up for resume_guest_state_on_host_boot).

Closes-Bug: #1462991
Change-Id: Id20e73c19543e3f4e240eee5c78e3f13ba466a2f

[Fuel Devops McRobotson (fuel-devops-robot)]

Reviewed: https://review.fuel-infra.org/9383
Submitter: Denis V. Meltsaykin <email address hidden>
Branch: openstack-ci/fuel-5.1.1-updates/2014.1.1

Commit: d08dde790374aafde2a78663fc2cee0df9c1f065
Author: Alex Ermolov <email address hidden>
Date: Mon Nov 16 21:28:52 2015

libvirt: Handle empty context on _hard_reboot

When _hard_reboot runs for resume_guest_state_on_host_boot, we don't
have a valid context. This checks if the context is valid before
attempting to repopulate base images.

This is a bit of a hack, as it assumes that the base images already
exist on the system, and will fail if they don't. However, it reduces
the number of failures (without this, every downed guest is guaranteed
to error when coming back up for resume_guest_state_on_host_boot).

Change-Id: Id20e73c19543e3f4e240eee5c78e3f13ba466a2f
Closes-Bug: #1462991