diff --git a/doc/source/system_configuration/openstack/configure-a-live-migration-parameters-in-nova-6154238dfc6d.rst b/doc/source/system_configuration/openstack/configure-a-live-migration-parameters-in-nova-6154238dfc6d.rst new file mode 100644 index 000000000..e59e87311 --- /dev/null +++ b/doc/source/system_configuration/openstack/configure-a-live-migration-parameters-in-nova-6154238dfc6d.rst @@ -0,0 +1,108 @@ +.. _configure-a-live-migration-parameters-in-nova-6154238dfc6d: + +=========================================== +Configure Live Migration Parameters in Nova +=========================================== + +.. rubric:: |context| + +You can configure a maximum time for a live migration to complete and/or the +maximum downtime target for live migration switchover. + +---------- +Parameters +---------- + +- ``live_migration_completion_timeout`` + + Time to wait, in seconds, for live migration to successfully complete + transferring data before aborting the operation. + + Value is per GiB of guest RAM + disk to be transferred, with a lower + boundary of 2 GiB. Set to 0 to disable timeouts. + +- ``live_migration_downtime`` + + The target maximum period of time that Nova will require the |VM| to be + paused in order to complete the |VM| memory copy. If the transfer rate + slows down after the |VM| has been paused, this value can be exceeded by a + small amount of time, it will be rounded up to a minimum of 100ms. + + You may increase this value if you want to allow live-migrations to + complete faster, or avoid ``live-migration`` timeout errors by allowing the + guest to be paused longer during the ``live-migration`` switch over. + + Two additional ``live_migration_downtime_scope`` parameters can be + modified: + + - ``live_migration_downtime_steps`` + + Sets the total number of adjustment steps until + ``live_migration_downtime`` is reached. This will let nova increase + ``live_migration_downtime`` gradually until either the switchover has + been completed or the maximum value has been reached. The default is 10 + steps. + + - ``live_migration_downtime_delay`` + + Sets the time interval between two adjustment steps in seconds. The + default is 75. + +.. rubric:: |proc| + +All the parameters can be modified using the Helm overrides for the |prod-os| +application. + +#. Create a yaml file containing the configuration update. + + For example ``nova_override.yaml``: + + .. code-block:: none + + conf: + nova: + libvirt: + live_migration_completion_timeout: 300 + live_migration_downtime: 600 + live_migration_downtime_steps: 12 + live_migration_downtime_delay: 50 + +#. Update the Helm overrides using the new configuration file. + + .. code-block:: none + + ~(keystone_admin)]$ system helm-override-update --values ./nova_override.yaml wr-openstack nova openstack --reuse-values + +#. Confirm that the user override lists the correct live migration parameters. + + .. code-block:: none + + ~(keystone_admin)]$ system helm-override-show wr-openstack nova openstack + +#. Apply the changes. + + .. code-block:: none + + ~(keystone_admin)]$ system application-apply wr-openstack + +.. rubric:: |result| + +If the live migration aborts because ``live_migration_completion_timeout`` has +been exceeded, then the following message appears on the ``nova_compute`` logs: + +.. code-block:: none + + WARNING nova.virt.libvirt.migration [-] [instance: 07b5842b-6324-4de0-973e-6d0ff18ef574] Live migration not completed after 300 seconds + +The default behavior is to abort the operation. You can change this action by +configuring ``live_migration_timeout_action`` in your yaml file. + +For example: + +.. code-block:: none + + live_migration_timeout_action: force_complete + +If it is set to ``force_complete``, the compute service will either pause the +|VM| or trigger post-copy if post copy is enabled and available +(``live_migration_permit_post_copy`` is set to True). diff --git a/doc/source/system_configuration/openstack/configuring-a-live-migration-completion-timeout-in-nova.rst b/doc/source/system_configuration/openstack/configuring-a-live-migration-completion-timeout-in-nova.rst deleted file mode 100644 index bd3ef11b5..000000000 --- a/doc/source/system_configuration/openstack/configuring-a-live-migration-completion-timeout-in-nova.rst +++ /dev/null @@ -1,57 +0,0 @@ - -.. err1590511228224 -.. _configuring-a-live-migration-completion-timeout-in-nova: - -===================================================== -Configure a Live Migration Completion Timeout in Nova -===================================================== - -You can configure how long to allow for a compute live migration to -complete before the operation is aborted. - -.. rubric:: |context| - -The following example applies a timeout of 300 seconds to all hosts. - -The same basic workflow of *creating an overrides file*, then -*using it to update helm overrides for the application*, and finally -*reapplying the application to make your changes effective* can be used -to apply other Nova overrides globally. - -.. rubric:: |proc| - -#. Create a yaml configuration file containing the configuration update. - - .. code-block:: none - - ~(keystone_admin)]$ cat << EOF > ./nova_override.yaml - conf: - nova: - libvirt: - live_migration_completion_timeout: 300 - EOF - - -#. Update the Helm overrides using the new configuration file. - - .. parsed-literal:: - - ~(keystone_admin)]$ system helm-override-update --reuse-values --values ./nova_override.yaml |prefix|-openstack nova openstack --reuse-values - -#. Confirm that the user\_override lists the correct live migration completion timeout. - - .. parsed-literal:: - - ~(keystone_admin)$ system helm-override-show |prefix|-openstack nova openstack - - The output should include the following: - - .. code-block:: none - - live_migration_completion_timeout: 300 - -#. Apply the changes. - - .. parsed-literal:: - - ~(keystone_admin)]$ system application-apply |prefix|-openstack \ No newline at end of file diff --git a/doc/source/system_configuration/openstack/index-sysconf-os-988a21c687cb.rst b/doc/source/system_configuration/openstack/index-sysconf-os-988a21c687cb.rst index b11a79648..db6fc3b67 100644 --- a/doc/source/system_configuration/openstack/index-sysconf-os-988a21c687cb.rst +++ b/doc/source/system_configuration/openstack/index-sysconf-os-988a21c687cb.rst @@ -16,7 +16,7 @@ Configure OpenStack Services Using Helm Chart Overrides :maxdepth: 1 system-configuration-overview - configuring-a-live-migration-completion-timeout-in-nova + configure-a-live-migration-parameters-in-nova-6154238dfc6d configuring-a-pci-alias-in-nova configuring-the-rpc-response-timeout-in-cinder configure-the-nfs-backend-on-cinder-backup