Creating a Node¶
Prerequisites¶
At least one cluster has been created.
A key pair has been created for identity authentication upon remote node login.
Notes and Constraints¶
The DNS configuration of a subnet where a node is located cannot be modified because OBS and other dependent services are necessary for creating nodes.
Precautions¶
To maintain node stability, Kubernetes components such as kubelet, kube-proxy, and docker, as well as the Kubernetes system, will be allocated a specific number of node resources based on the node flavor. Therefore, the total number of node resources and the number of allocatable node resources for your cluster are different. The larger the node specifications, the more the containers deployed on the node. Therefore, more node resources need to be reserved to run Kubernetes components. For details, see Node Resource Reservation Policy.
Networks including VM networks and container networks of nodes are all managed by CCE. Do not add or delete ENIs, or change routes and IP addresses. Otherwise, services may be unavailable. For example, the ENI named gw_11cbf51a@eth0 on the node is the container network gateway and cannot be modified.
Procedure¶
After a cluster is created, you can create nodes for the cluster.
Log in to the CCE console.
In the navigation pane of the CCE console, choose Clusters. Click the target cluster name to access its details page.
In the navigation pane, choose Nodes. On the page displayed, click the Nodes tab and then Create Node in the upper right corner. Configure node parameters.
Configurations
You can configure the flavor and OS of a cloud server, on which your containerized applications run.
Table 1 Node configuration parameters¶ Parameter
Description
AZ
AZ where the node is located. Nodes in a cluster can be created in different AZs for higher reliability. The value cannot be changed after the node is created.
Select Random to deploy your node in a random AZ based on the selected node flavor.
An AZ is a physical region where resources use independent power supply and networks. AZs are physically isolated but interconnected through an internal network. To enhance workload availability, create nodes in different AZs.
Node Type
Select a node type based on service requirements. Then, the available node flavors will be automatically displayed in the Specifications area for you to select.
CCE standard clusters support the following node types:
ECS (VM): A virtualized ECS is used as a cluster node.
Specifications
Select node flavors as needed. A node needs at least two vCPU cores and 4 GiB of memory.
The available node flavors vary depending on AZs. Obtain the flavors displayed on the console.
Container Engine
The container engines supported by CCE include Docker and containerd, which may vary depending on cluster types, cluster versions, and OSs. Select a container engine based on the information displayed on the CCE console. For details, see Mapping between Node OSs and Container Engines.
OS
Select an OS type. Different types of nodes support different OSs.
Public image: Select a public image for the node.
Private image: Select a private image for the node.
Note
Service container runtimes share the kernel and underlying calls of nodes. To ensure compatibility, select a Linux distribution version that is the same as or close to that of the final service container image for the node OS.
Node Name
Name of the node. When nodes (ECSs) are created in batches, the value of this parameter is used as the name prefix for each ECS.
The system generates a default name for you, which can be modified.
Enter 1 to 56 characters. Only lowercase letters, digits, hyphens (-), and periods (.) are allowed. The name must start with a lowercase letter and cannot end with a hyphen (-). Only lowercase letters or digits are allowed before and after periods (.).
Login Mode
Key Pair
Select the key pair used to log in to the node. You can select a shared key.
A key pair is used for identity authentication when you remotely log in to a node. If no key pair is available, click Create Key Pair.
Storage Settings
Configure storage resources on a node for the containers running on it. Select a disk type and configure its size based on service requirements.
Table 2 Storage configuration parameters¶ Parameter
Description
System Disk
System disk used by the node OS. The value ranges from 40 GiB to 1024 GiB. The default value is 50 GiB.
Encryption: System disk encryption safeguards your data. Snapshots generated from encrypted disks and disks created using these snapshots automatically inherit the encryption setting. Only the nodes of the Elastic Cloud Server (VM) type in certain regions support system disk encryption. For details, see the console.
Not encrypted is selected by default.
If you select Enabled (key) for System Disk Encryption, choose an existing key. If no key is available, click View Key List and create a key. After the key is created, click the refresh icon next to the text box.
If you select Enabled (KMS key ID) for System Disk Encryption, enter a KMS key (which can be shared by others) in the current region.
Data Disk
At least one data disk is required for the container runtime and kubelet. The data disk cannot be deleted or uninstalled. Otherwise, the node will be unavailable.
First data disk: used for container runtime and kubelet components. The value ranges from 20 GiB to 32768 GiB. The default value is 100 GiB.
Other data disks: You can set the data disk size to a value ranging from 10 GiB to 32768 GiB. The default value is 100 GiB.
Note
If the node flavor is disk-intensive or ultra-high I/O, one data disk can be a local disk.
Local disks may break down and do not ensure data reliability. Store your service data in EVS disks, which are more reliable than local disks.
Advanced Settings
Expand the area and configure the following parameters:
Data Disk Space Allocation: allocates space for container engines, images, and ephemeral storage for them to run properly. For details about how to allocate data disk space, see Data Disk Space Allocation.
Data Disk Encryption: Data disk encryption safeguards your data. Snapshots generated from encrypted disks and disks created using these snapshots automatically inherit the encryption setting.
Not encrypted is selected by default.
If you select Enabled (key) for Data Disk Encryption, choose an existing key. If no key is available, click View Key List and create a key. After the key is created, click the refresh icon next to the text box.
If you select Enabled (KMS key ID) for Data Disk Encryption, enter a KMS key (which can be shared by others) in the current region.
Adding data disks
A maximum of 16 data disks can be attached to an ECS. By default, a raw disk is created without any processing. You can also click Expand and select any of the following options:
Default: By default, a raw disk is created without any processing.
Mount Disk: The data disk is attached to a specified directory.
Use as PV: applicable when there is a high performance requirement on PVs. The node.kubernetes.io/local-storage-persistent label is added to the node with PV configured. The value is linear or striped.
Use as ephemeral volume: applicable when there is a high performance requirement on emptyDir.
Note
Local PVs are supported only when the cluster version is v1.21.2-r0 or later and the Everest add-on version is 2.1.23 or later. Version 2.1.23 or later is recommended.
Local EVs are supported only when the cluster version is v1.21.2-r0 or later and the Everest add-on version is 1.2.29 or later.
Local PVs and local EVs can be written in the following modes:
Linear: A linear logical volume integrates one or more physical volumes. Data is written to the next physical volume when the previous one is used up.
Striped: A striped logical volume stripes data into blocks of the same size and stores them in multiple physical volumes in sequence. This allows data to be concurrently read and written. A storage pool consisting of striped volumes cannot be scaled-out. This option can be selected only when multiple volumes exist.
Network Settings
Configure networking resources to allow node and containerized application access.
Table 3 Configuration parameters¶ Parameter
Description
VPC/Node Subnet
The node subnet selected during cluster creation is used by default. You can choose another subnet instead.
Node IP Address
IP address of the specified node. By default, the value is randomly allocated.
EIP
An ECS without a bound EIP cannot access the Internet or be accessed by public networks.
The default value is Do not use. Use existing and Auto create are supported.
Advanced Settings
Configure advanced node capabilities such as labels, taints, and startup command.
Table 4 Advanced configuration parameters¶ Parameter
Description
Resource Tag
You can add resource tags to classify resources. A maximum of eight resource tags can be added.
You can create predefined tags on the TMS console. The predefined tags are available to all resources that support tags. You can use predefined tags to improve the tag creation and resource migration efficiency.
CCE will automatically create the "CCE-Dynamic-Provisioning-Node=Node ID" tag.
Kubernetes Label
A key-value pair added to a Kubernetes object (such as a pod). After specifying a label, click Add Label for more. A maximum of 20 labels can be added.
Labels can be used to distinguish nodes. With workload affinity settings, pods can be scheduled to a specified node. For more information, see Labels and Selectors.
Taint
This parameter is left blank by default. You can add taints to configure anti-affinity for the node. A maximum of 20 taints are allowed for each node. Each taint contains the following parameters:
Key: A key must contain 1 to 63 characters, starting with a letter or digit. Only letters, digits, hyphens (-), underscores (_), and periods (.) are allowed. A DNS subdomain name can be used as the prefix of a key.
Value: A value must contain 1 to 63 characters, starting with a letter or digit. Only letters, digits, hyphens (-), underscores (_), and periods (.) are allowed.
Effect: Available options are NoSchedule, PreferNoSchedule, and NoExecute.
For details, see Managing Node Taints.
Note
For a cluster of v1.19 or earlier, the workload may have been scheduled to a node before the taint is added. To avoid such a situation, select a cluster of v1.19 or later.
Max. Pods
Maximum number of pods that can run on the node, including the default system pods.
This limit prevents the node from being overloaded with pods.
This number is also decided by other factors. For details, see Maximum Number of Pods That Can Be Created on a Node.
ECS Group
An ECS group logically groups ECSs. The ECSs in the same ECS group comply with the same policy associated with the ECS group.
Anti-affinity: ECSs in an ECS group are deployed on different physical hosts to improve service reliability.
Select an existing ECS group, or click Add ECS Group to create one. After the ECS group is created, click the refresh icon.
Pre-installation Command
Pre-installation script command, in which Chinese characters are not allowed. The script command will be Base64-transcoded. The characters of both the pre-installation and post-installation scripts are centrally calculated, and the total number of characters after transcoding cannot exceed 10240.
The script will be executed before Kubernetes software is installed. Note that if the script is incorrect, Kubernetes software may fail to be installed.
Post-installation Command
Pre-installation script command, in which Chinese characters are not allowed. The script command will be Base64-transcoded. The characters of both the pre-installation and post-installation scripts are centrally calculated, and the total number of characters after transcoding cannot exceed 10240.
The script will be executed after Kubernetes software is installed, which does not affect the installation.
Note
Do not run the reboot command in the post-installation script to restart the system immediately. To restart the system, run the shutdown -r 1 command to restart with a delay of one minute.
Agency
An agency is created by the account administrator on the IAM console. Using an agency, you can share your cloud server resources with another account, or entrust a more professional person or team to manage your resources.
If no agency is available, click Create Agency on the right to create one.
Configure the number of nodes to be created. Then, click Next: Confirm. Confirm the configured parameters and specifications.
Click Submit.
The node list page is displayed. If the node status is Running, the node is created successfully. It takes about 6 to 10 minutes to create a node.
Click Back to Node List. The node is created successfully if it changes to the Running state.