Chapter 11. Configuring manual node reboot to define KernelArgs
Chapter 11. Configuring manual node reboot to define KernelArgs Overcloud nodes are automatically rebooted when the overcloud deployment includes setting the KernelArgs for the first time. Rebooting nodes can be an issue for existing workloads if you are adding KernelArgs to a deployment that is already in production. You can disable the automatic rebooting of nodes when updating a deployment, and instead perform node reboots manually after each overcloud deployment. Note If you disable automatic reboot and then add new Compute nodes to your deployment, the new nodes will not be rebooted during their initial provisioning. This might cause deployment errors because the configuration of KernelArgs is applied only after a reboot. 11.1. Configuring manual node reboot to define KernelArgs You can disable the automatic rebooting of nodes when you configure KernelArgs for the first time, and instead reboot the nodes manually. Procedure Log in to the undercloud as the stack user. Source the stackrc file: Enable the KernelArgsDeferReboot role parameter in a custom environment file, for example, kernelargs_manual_reboot.yaml : Add your custom environment file to the stack with your other environment files and deploy the overcloud: Retrieve a list of your Compute nodes to identify the host name of the node that you want to reboot: Disable the Compute service on the Compute node you want to reboot, to prevent the Compute scheduler from assigning new instances to the node: Replace <node> with the host name of the node you want to disable the Compute service on. Retrieve a list of the instances hosted on the Compute node that you want to migrate: Migrate the instances to another Compute node. For information on migrating instances, see Migrating virtual machine instances between Compute nodes . Log in to the node that you want to reboot. Reboot the node: Wait until the node boots. Re-enable the Compute node: Check that the Compute node is enabled:
[stack@director ~]USD source ~/stackrc parameter_defaults: <Role>Parameters: KernelArgsDeferReboot: True (undercloud)USD openstack overcloud deploy --templates -e [your environment files] -e /home/stack/templates/kernelargs_manual_reboot.yaml (undercloud)USD source ~/overcloudrc (overcloud)USD openstack compute service list (overcloud)USD openstack compute service set <node> nova-compute --disable (overcloud)USD openstack server list --host <node_UUID> --all-projects [heat-admin@overcloud-compute-0 ~]USD sudo reboot (overcloud)USD openstack compute service set <node_UUID> nova-compute --enable (overcloud)USD openstack compute service list