Julia Kreger
f84d5917c6
This patch is based upon a downstream patch which came up in discussion amongst the ironic community when some operators began discussing a case where resource providers had disappeared from a running deployment with several thousand baremetal nodes. Discussion amongst operators and developers ensued and we were able to determine that this was still an issue in the current upstream code and that time difference between collecting data and then reconciling the records was a source of the issue. Per Arun, they have been running this change downstream and had not seen any reoccurances of the issue since the patch was applied. This patch was originally authored by Arun S A G, and below is his original commit mesage. An instance could be launched and scheduled to a compute node between get_uuids_by_host() call and _get_node_list() call. If that happens the ironic node.instance_uuid may not be None but the instance_uuid will be missing from the instance list returned by get_uuids_by_host() method. This is possible because _get_node_list() takes several minutes to return in large baremetal clusters and a lot can happen in that time. This causes the compute node to be orphaned and associated resource provider to be deleted from placement. Once the resource provider is deleted it is never created again until the service restarts. Since resource provider is deleted subsequent boots/rebuilds to the same host will fail. This behaviour is visibile in VMbooter nodes because it constantly launches and deletes instances there by increasing the likelihood of this race condition happening in large ironic clusters. To reduce the chance of this race condition we call _get_node_list() first followed by get_uuids_by_host() method. Change-Id: I55bde8dd33154e17bbdb3c4b0e7a83a20e8487e8 Co-Authored-By: Arun S A G <saga@yahoo-inc.com> Related-Bug: #1841481
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OpenStack Nova
==============
.. image:: https://governance.openstack.org/tc/badges/nova.svg
:target: https://governance.openstack.org/tc/reference/tags/index.html
.. Change things from this point on
OpenStack Nova provides a cloud computing fabric controller, supporting a wide
variety of compute technologies, including: libvirt (KVM, Xen, LXC and more),
Hyper-V, VMware, OpenStack Ironic and PowerVM.
Use the following resources to learn more.
API
---
To learn how to use Nova's API, consult the documentation available online at:
- `Compute API Guide <https://docs.openstack.org/api-guide/compute/>`__
- `Compute API Reference <https://docs.openstack.org/api-ref/compute/>`__
For more information on OpenStack APIs, SDKs and CLIs in general, refer to:
- `OpenStack for App Developers <https://www.openstack.org/appdev/>`__
- `Development resources for OpenStack clouds
<https://developer.openstack.org/>`__
Operators
---------
To learn how to deploy and configure OpenStack Nova, consult the documentation
available online at:
- `OpenStack Nova <https://docs.openstack.org/nova/>`__
In the unfortunate event that bugs are discovered, they should be reported to
the appropriate bug tracker. If you obtained the software from a 3rd party
operating system vendor, it is often wise to use their own bug tracker for
reporting problems. In all other cases use the master OpenStack bug tracker,
available at:
- `Bug Tracker <https://bugs.launchpad.net/nova>`__
Developers
----------
For information on how to contribute to Nova, please see the contents of the
CONTRIBUTING.rst.
Any new code must follow the development guidelines detailed in the HACKING.rst
file, and pass all unit tests.
Further developer focused documentation is available at:
- `Official Nova Documentation <https://docs.openstack.org/nova/>`__
- `Official Client Documentation
<https://docs.openstack.org/python-novaclient/>`__
Other Information
-----------------
During each `Summit`_ and `Project Team Gathering`_, we agree on what the whole
community wants to focus on for the upcoming release. The plans for nova can
be found at:
- `Nova Specs <http://specs.openstack.org/openstack/nova-specs/>`__
.. _Summit: https://www.openstack.org/summit/
.. _Project Team Gathering: https://www.openstack.org/ptg/