Node labels are mainly used in the following scenarios:

Node management: Node labels are used to classify nodes.
Affinity and anti-affinity between a workload and node:
- Some workloads require a large CPU, some require a large memory, some require a large I/O, and other workloads may be affected. In this case, you are advised to add different labels to nodes. When deploying a workload, you can select nodes with specified labels for affinity deployment to ensure the normal operation of the system. Otherwise, node anti-affinity deployment can be used.
- A system can be divided into multiple modules. Each module consists of multiple microservices. To ensure the efficiency of subsequent O&M, you can add a module label to each node so that each module can be deployed on the corresponding node, does not interfere with other modules, and can be easily developed and maintained on its node.

After a node is created, some fixed labels exist and cannot be deleted. For details about these labels, see Table 1.

**Table 1** Inherent label of a node
Key	Description
New: topology.kubernetes.io/region Old: failure-domain.beta.kubernetes.io/region	Region where the node is located
New: topology.kubernetes.io/zone Old: failure-domain.beta.kubernetes.io/zone	AZ where the node is located
New: node.kubernetes.io/baremetal Old: failure-domain.beta.kubernetes.io/is-baremetal	Whether the node is a bare metal node false indicates that the node is not a bare metal node.
node.kubernetes.io/instance-type	Node specifications
kubernetes.io/arch	Node processor architecture
kubernetes.io/hostname	Node name
kubernetes.io/os	OS type
node.kubernetes.io/subnetid	ID of the subnet where the node is located.
os.architecture	Node processor architecture For example, amd64 indicates a AMD64-bit processor.
os.name	Node OS name
os.version	Node OS kernel version

Log in to the CCE console. In the navigation pane, choose Resource Management > Nodes.
In the same row as the node for which you will add labels, choose Operation > More > Manage Labels.
In the dialog box displayed, click Add Label below the label list, enter the key and value of the label to be added, and click OK.
As shown in the figure, the key is deploy_qa and the value is true, indicating that the node is used to deploy the QA (test) environment.
After the label is added, click Manage Labels. Then, you will see the label that you have added.

Only labels added by users can be deleted. Labels that are fixed on the node cannot be deleted.

Log in to the CCE console. In the navigation pane, choose Resource Management > Nodes.
In the same row as the node for which you will delete labels, choose Operation > More > Manage Labels.
Click Delete, and then click OK to delete the label.
Label updated successfully is displayed.

Log in to the CCE console. In the navigation pane, choose Resource Management > Nodes.
In the upper right corner of the node list, click Search by Label.
Enter a Kubernetes label to find the target node.

Managing Node Labels