Assign Node Labels from the CLI

You can assign labels to affect the scheduling of Kubernetes objects, such as pods.

Prerequisites

Hosts must be locked before labels can be assigned.

Labels are key/value pairs that are attached to nodes and are used to specify identifying attributes of nodes. Labels can be used to identify physical attributes of a node such as special purpose hardware or labels can be used to identify logical attributes of a node, for example the role of a node.

To change the value of a label, you must remove and reapply it. For more information, see Remove Node Labels from the CLI.

For more information on labels that are used to assign pods to nodes, refer to https://kubernetes.io/docs/concepts/configuration/assign-pod-node/.

Procedure

To assign a label to a host, use the host-label-assign command.

This command accepts a list of labels to assign. There can be one or many key-value pairs. Each added label will be returned.

The command format is:

system host-label-assign (<hostName> | <hostID>) <key>=<value> [<key>=<value> ...]

For example:

~(keystone)admin)$ system host-label-assign controller-0 openstack-compute-node=enabled openvswitch=enabled sriov=enabled
+-------------+--------------------------------------+
| Property    | Value                                |
+-------------+--------------------------------------+
| uuid        | 2909d775-cd6c-4bc1-8268-27499fe38d5e |
| host_uuid   | 1f00d8a4-f520-41ee-b608-1b50054b1cd8 |
| label_key   | openstack-compute-node               |
| label_value | enabled                              |
+-------------+--------------------------------------+
+-------------+--------------------------------------+
| Property    | Value                                |
+-------------+--------------------------------------+
| uuid        | 8dafcfcf-e417-4fd0-8829-8baadb3a3981 |
| host_uuid   | 1f00d8a4-f520-41ee-b608-1b50054b1cd8 |
| label_key   | openvswitch                          |
| label_value | enabled                              |
+-------------+--------------------------------------+
+-------------+--------------------------------------+
| Property    | Value                                |
+-------------+--------------------------------------+
| uuid        | d8e29e62-4173-4445-886c-9a95b0d6fee1 |
| host_uuid   | 1f00d8a4-f520-41ee-b608-1b50054b1cd8 |
| label_key   | SRIOV                                |
| label_value | enabled                              |
+-------------+--------------------------------------+

Note

You can look up host names and IDs using the host-list command.