Updated on 2024-11-14 GMT+08:00

Quick Start

Overview

The bursting add-on functions as a virtual kubelet to connect Kubernetes clusters to APIs of other platforms. This add-on is mainly used to extend Kubernetes APIs to serverless container services such as Huawei Cloud CCI.

With this add-on, you can schedule Deployments, StatefulSets, jobs, and CronJobs running in CCE clusters to CCI during peak hours. In this way, you can reduce consumption caused by cluster scaling.

Constraints

  • Only CCE standard and CCE Turbo clusters that use the VPC network mode are supported. Arm clusters are not supported. Add-on instances will not be deployed on Arm nodes, if any, running in the cluster.
  • DaemonSets and pods that use the HostNetwork mode cannot be scheduled to CCI.
  • The subnet where the cluster is located cannot overlap with 10.247.0.0/16, or the subnet conflicts with the Service CIDR block in the CCI namespace.
  • Currently, Volcano cannot be used to schedule pods with cloud storage volumes mounted to CCI.

Precautions

  • Before using the add-on, go to the CCI console to grant CCI with the permissions to use CCE.
  • After the add-on is installed, a namespace named cce-burst-{Cluster ID} will be created in CCI and managed by the add-on. Do not use this namespace when manually creating pods in CCI.

Installing the Add-on

  1. Log in to the CCE console.
  2. Click the name of the target CCE cluster to go to the cluster console.
  3. In the navigation pane, choose Add-ons.
  4. Select the CCE Cloud Bursting Engine for CCI add-on and click Install.
  5. Configure the add-on parameters.

    Table 1 Add-on parameters

    Parameter

    Description

    Version

    Add-on version. There is a mapping between add-on versions and CCE cluster versions. For more details, see "Change History" in CCE Cloud Bursting Engine for CCI.

    Specifications

    Number of pods required for running the add-on.

    • If you select Preset, you can select Single or HA.
    • If you select Custom, you can modify the number of replicas, vCPUs, and memory of each add-on component as required.
    NOTE:
    • The bursting add-on 1.5.2 or later uses more node resources. You need to reserve sufficient pods before upgrading the add-on.
      • Single (only one pod for the add-on): There must be a node that has at least seven schedulable pods. If Networking is enabled, eight schedulable pods are required.
      • HA (two pods for the add-on): There must be two nodes, each of which must have at least seven schedulable pods, a total of 14 schedulable pods. If Networking is enabled, eight schedulable pods are required on each node, a total of 16 schedulable pods.
    • The resource usage of the add-on varies depending on the workloads scaled to CCI. The pods, secrets, ConfigMaps, PVs, and PVCs requested by the services occupy VM resources. You are advised to evaluate the service usage and apply for VMs based on the following specifications: For 1,000 pods and 1,000 ConfigMaps (300 KB), nodes with 2 vCPUs and 4-GiB memory are recommended. For 2,000 pods and 2,000 ConfigMaps, nodes with 4 vCPUs and 8-GiB memory are recommended. For 4,000 pods and 4,000 ConfigMaps, nodes with 8 vCPUs and 16-GiB memory are recommended.

    Networking

    If this option is enabled, pods in the CCE cluster can communicate with pods in CCI through Services. The component proxy will be automatically deployed upon add-on installation. For details, see Networking.

Creating a Workload

  1. Log in to the CCE console.
  2. Click the name of the target CCE cluster to go to the cluster console.
  3. In the navigation pane, choose Workloads.
  4. Click Create Workload. For details, see Creating a Workload.
  5. Specify basic information. Set Burst to CCI to Force scheduling. For more information about scheduling policies, see Scheduling Pods to CCI.

    When you schedule a workload in a CCE cluster to CCI, TCP probes cannot be used for health check.

  6. Configure the container parameters.
  7. Click Create Workload.
  8. On the Workloads page, click the name of the created workload to go to the workload details page.
  9. View the node where the workload is running. If the workload is running on a CCI node, it has been scheduled to CCI.

Uninstalling the Add-on

  1. Log in to the CCE console.
  2. Click the name of the target CCE cluster to go to the cluster console.
  3. In the navigation pane, choose Add-ons.
  4. Select the CCE Cloud Bursting Engine for CCI add-on and click Uninstall.

    Table 2 Special scenarios for uninstalling the add-on

    Scenario

    Symptom

    Description

    There are no nodes in the CCE cluster that the bursting add-on needs to be uninstalled from.

    Failed to uninstall the bursting add-on.

    If the bursting add-on is uninstalled from the cluster, a job for clearing resources will be started in the cluster. To ensure that the job can be started, there is at least one node in the cluster that can be scheduled.

    The CCE cluster is deleted, but the bursting add-on is not uninstalled.

    There are residual resources in the namespace on CCI. If the resources are not free, additional expenditures will be generated.

    The cluster is deleted, but the resource clearing job is not executed. You can manually clear the namespace and residual resources.

    For more information about the bursting add-on, see CCE Cloud Bursting Engine for CCI.