Reboot a compute node

Reboot a compute node

This section instructs you on how to reboot an OpenStack compute node for a planned maintenance.

To reboot an OpenStack compute node:

  1. Log in to an OpenStack controller node.

  2. Disable scheduling of new VMs to the node. Optionally provide a reason comment:

    openstack compute service set --disable --disable-reason \
    maintenance <compute_node_hostname> nova-compute
    
  3. Migrate workloads from the OpenStack compute node:

    nova host-evacuate-live <compute_node_hostname>
    
  4. Log in to an OpenStack compute node.

  5. Stop the nova-compute service:

    service nova-compute stop
    
  6. Shut down the OpenStack compute node, perform the maintenance, and turn the node back on.

  7. Verify that the nova-compute service is up and running:

    service nova-compute status
    
  8. Perform the following steps from the OpenStack controller node:

    1. Enable scheduling of VMs to the node:

      openstack compute service set --enable <compute_node_hostname> nova-compute
      
    2. Verify that the nova-compute service and neutron agents are running on the node:

      openstack network agent list --host <compute_node_hostname>
      openstack compute service list --host <compute_node_hostname>
      

      The OpeStack compute service state must be up. The Neutron agent service state must be UP and the alive column must include :-).

      Examples of a positive system response:

      +----+--------------+------+------+---------+-------+----------------------------+
      | ID | Binary       | Host | Zone | Status  | State | Updated At                 |
      +----+--------------+------+------+---------+-------+----------------------------+
      | 70 | nova-compute | cmp1 | nova | enabled | up    | 2020-09-17T08:51:07.000000 |
      +----+--------------+------+------+---------+-------+----------------------------+
      
      +----------+--------------------+------+-------------------+-------+-------+---------------------------+
      | ID       | Agent Type         | Host | Availability Zone | Alive | State | Binary                    |
      +----------+--------------------+------+-------------------+-------+-------+---------------------------+
      | e4256d73 | Open vSwitch agent | cmp1 | None              | :-)   | UP    | neutron-openvswitch-agent |
      +----------+--------------------+------+-------------------+-------+-------+---------------------------+
      
    3. Optional. Migrate the instances back to their original OpenStack compute node.