From 80ad7d9df6a84c54099fff4cdf979d52a8179413 Mon Sep 17 00:00:00 2001 From: Sean Mooney Date: Wed, 6 Feb 2019 15:56:38 +0000 Subject: [PATCH] update flavor admin docs - This change updates the admin flavor docs to reflect the use of osc to update flavor descriptions - This change documents that modifcations to flavor extra_specs are not reflected in an instance's embedded flavor. Change-Id: I0f206d9db70465d8ce6b1404f546f3e00eeb6e23 --- doc/source/admin/flavors.rst | 23 ++++++++++++++++++++--- 1 file changed, 20 insertions(+), 3 deletions(-) diff --git a/doc/source/admin/flavors.rst b/doc/source/admin/flavors.rst index d59730a623c8..cb3d92f5fe91 100644 --- a/doc/source/admin/flavors.rst +++ b/doc/source/admin/flavors.rst @@ -111,12 +111,29 @@ and a new description as follows: .. code-block:: console - $ nova flavor-update FLAVOR DESCRIPTION + $ openstack flavor set --description .. note:: - There are no commands to update a description of a flavor - in the :command:`openstack` command currently (version 3.15.0). + The only field that can be updated is the description field. + Nova has historically intentionally not included an API to update + a flavor because that would be confusing for instances already + created with that flavor. Needing to change any other aspect of + a flavor requires deleting and/or creating a new flavor. + + Nova stores a serialized version of the flavor associated with an + instance record in the ``instance_extra`` table. While nova supports + `updating flavor extra_specs`_ it does not update the embedded flavor + in existing instances. Nova does not update the embedded flavor + as the extra_specs change may invalidate the current placement + of the instance or alter the compute context that has been + created for the instance by the virt driver. For this reason + admins should avoid updating extra_specs for flavors used by + existing instances. A resize can be used to update existing + instances if required but as a resize performs a cold migration + it is not transparent to a tenant. + +.. _updating flavor extra_specs: https://developer.openstack.org/api-ref/compute/?expanded=#update-an-extra-spec-for-a-flavor Delete a flavor ---------------