Bug 2013329

Summary:	[Ironic controller replacement] Disable nova-compute on the controller before replacement
Product:	Red Hat OpenStack	Reporter:	Artom Lifshitz <alifshit>
Component:	documentation	Assignee:	RHOS Documentation Team <rhos-docs>
Status:	CLOSED DUPLICATE	QA Contact:	RHOS Documentation Team <rhos-docs>
Severity:	unspecified	Docs Contact:
Priority:	unspecified
Version:	16.1 (Train)	CC:	igallagh
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Fixed In Version:		Doc Type:	If docs needed, set a value
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Last Closed:	2021-10-28 13:47:43 UTC	Type:	Bug
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oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
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Embargoed:
Bug Depends On:	2017980
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Description Artom Lifshitz 2021-10-12 15:25:29 UTC

Description of problem:

Following up BZ 1986406, it seems our doc don't tell to migrate workloads off the to-be-replaced controllers nodes. This would be nonsensical in a libvirt context, but with Ironic, nova-compute services are running on the controllers, so the workloads that they host need to migrated.

For example, in BZ 1986406, they cannot delete an old nova-compute service db entry because it has no compute nodes associated with it (as they've been rebalanced by Ironic to other nova-computes), but they still have instances that have the `host` field set to the old controller hostnames.

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Comment 1 Artom Lifshitz 2021-10-27 20:15:45 UTC

Once BZ 2017980 is done, we can update the documentation to state that for the Ironic controller replacement case, nova-compute services on the to-be-replaced controller needs to be disabled, and then the Ironic periodic rebalance needs to happen to re-assign any instances on that host to other hosts. Until then, nothing much to do.

Comment 2 Artom Lifshitz 2021-10-28 13:47:43 UTC


*** This bug has been marked as a duplicate of bug 1986406 ***