Chapter 7. Rebooting the overcloud after the upgrade
After upgrading your Red Hat OpenStack environment, reboot your overcloud. The reboot updates the nodes with any associated kernel, system-level, and container component updates. These updates may provide performance and security benefits.
Plan downtime to perform the following reboot procedures.
7.1. Rebooting controller and composable nodes Copy linkLink copied to clipboard!
The following procedure reboots controller nodes and standalone nodes based on composable roles. This excludes Compute nodes and Ceph Storage nodes.
Procedure
- Log in to the node that you want to reboot.
Optional: If the node uses Pacemaker resources, stop the cluster:
[heat-admin@overcloud-controller-0 ~]$ sudo pcs cluster stopReboot the node:
[heat-admin@overcloud-controller-0 ~]$ sudo reboot- Wait until the node boots.
Check the services. For example:
If the node uses Pacemaker services, check that the node has rejoined the cluster:
[heat-admin@overcloud-controller-0 ~]$ sudo pcs statusIf the node uses Systemd services, check that all services are enabled:
[heat-admin@overcloud-controller-0 ~]$ sudo systemctl status- Repeat these steps for all Controller and composable nodes.
7.2. Rebooting a Ceph Storage (OSD) cluster Copy linkLink copied to clipboard!
The following procedure reboots a cluster of Ceph Storage (OSD) nodes.
Procedure
Log in to a Ceph MON or Controller node and disable Ceph Storage cluster rebalancing temporarily:
$ sudo ceph osd set noout $ sudo ceph osd set norebalance- Select the first Ceph Storage node to reboot and log into it.
Reboot the node:
$ sudo reboot- Wait until the node boots.
Log in to a Ceph MON or Controller node and check the cluster status:
$ sudo ceph -sCheck that the
pgmapreports allpgsas normal (active+clean).- Log out of the Ceph MON or Controller node, reboot the next Ceph Storage node, and check its status. Repeat this process until you have rebooted all Ceph storage nodes.
When complete, log into a Ceph MON or Controller node and enable cluster rebalancing again:
$ sudo ceph osd unset noout $ sudo ceph osd unset norebalancePerform a final status check to verify the cluster reports
HEALTH_OK:$ sudo ceph status
7.3. Rebooting Compute nodes Copy linkLink copied to clipboard!
Rebooting a Compute node involves the following workflow:
- Select a Compute node to reboot and disable it so that it does not provision new instances.
- Migrate the instances to another Compute node to minimise instance downtime.
- Reboot the empty Compute node and enable it.
Procedure
-
Log in to the undercloud as the
stackuser. To identify the Compute node that you intend to reboot, list all Compute nodes:
$ source ~/stackrc (undercloud) $ openstack server list --name computeFrom the overcloud, select a Compute Node and disable it:
$ source ~/overcloudrc (overcloud) $ openstack compute service list (overcloud) $ openstack compute service set <hostname> nova-compute --disableList all instances on the Compute node:
(overcloud) $ openstack server list --host <hostname> --all-projects- Migrate your instances. For more information on migration strategies, see Migrating virtual machines between Compute nodes.
Log into the Compute Node and reboot it:
[heat-admin@overcloud-compute-0 ~]$ sudo reboot- Wait until the node boots.
Enable the Compute node:
$ source ~/overcloudrc (overcloud) $ openstack compute service set <hostname> nova-compute --enableVerify that the Compute node is enabled:
(overcloud) $ openstack compute service list
7.4. Rebooting Compute HCI nodes Copy linkLink copied to clipboard!
The following procedure reboots Compute hyperconverged infrastructure (HCI) nodes.
Procedure
Log in to a Ceph MON or Controller node and disable Ceph Storage cluster rebalancing temporarily:
$ sudo ceph osd set noout $ sudo ceph osd set norebalance-
Log in to the undercloud as the
stackuser. List all Compute nodes and their UUIDs:
$ source ~/stackrc (undercloud) $ openstack server list --name computeIdentify the UUID of the Compute node you aim to reboot.
From the undercloud, select a Compute node and disable it:
$ source ~/overcloudrc (overcloud) $ openstack compute service list (overcloud) $ openstack compute service set [hostname] nova-compute --disableList all instances on the Compute node:
(overcloud) $ openstack server list --host [hostname] --all-projectsUse one of the following commands to migrate your instances:
Migrate the instance to a specific host of your choice:
(overcloud) $ openstack server migrate [instance-id] --live [target-host]--waitLet
nova-schedulerautomatically select the target host:(overcloud) $ nova live-migration [instance-id]Live migrate all instances at once:
$ nova host-evacuate-live [hostname]NoteThe
novacommand might cause some deprecation warnings, which are safe to ignore.
- Wait until the migration completes.
Confirm that the migration was successful:
(overcloud) $ openstack server list --host [hostname] --all-projects- Continue migrating instances until none remain on the chosen Compute node.
Log in to a Ceph MON or a Controller node and check the cluster status:
$ sudo ceph -sCheck that the
pgmapreports allpgsas normal (active+clean).Reboot the Compute HCI node:
$ sudo reboot- Wait until the node boots.
Enable the Compute node again:
$ source ~/overcloudrc (overcloud) $ openstack compute service set [hostname] nova-compute --enableVerify that the Compute node is enabled:
(overcloud) $ openstack compute service list- Log out of the node, reboot the next node, and check its status. Repeat this process until you have rebooted all Ceph storage nodes.
When complete, log in to a Ceph MON or Controller node and enable cluster rebalancing again:
$ sudo ceph osd unset noout $ sudo ceph osd unset norebalancePerform a final status check to verify the cluster reports
HEALTH_OK:$ sudo ceph status