FAQ

KubeVela 是一个平台构建工具，用于创建基于 Kubernete 的易使用、可拓展的应用交付/管理系统。KubeVela 将 Helm 作为模板引擎和应用包的标准。但是 Helm 不是 KubeVela 唯一支持的模板模块。另一个同样最优先支持的是 CUE。

同时，KubeVale 被设计为 Kubernetes 的一个控制器（即工作在服务端）,即使是其 Helm 部分，也会安装一个 Helm Operator。

目前 KubeVela 中使用的 Crossplane 云资源数量支持比较有限的，是否有计划加快开发、增加云资源数量？

目前 KubeVela 支持 Crossplane 和 Terraform Controller 两种模式提供云资源，Terraform Controller 可以直接使用现成的 Terraform 模块，所以支持的云资源广度和数量都相对庞大，对于 Crossplane 不支持的云资源，可以考虑使用 Terraform Controller。目前 KubeVela 正在添加常用的云资源最佳实践用例，到 1.2 版本常用云资源都可以开箱即用。

另一方面，Crossplane 中阿里云的云资源支持也是由 KubeVela 的维护团队在负责维护，我们也非常乐意支持比较常用的云资源，在 Crossplane 项目中做更精细化的支持，所以比较倾向于使用 Crossplane 的用户可以在社区提 Issue 表达诉求，我们会根据用户的意愿确定开发计划。

Kubevela 未来具体要往哪个方向发展，是基于 GitOps 的 CD 工具，还是基于Workflow 的类似于 Tekton 或 Argo Worflow 这样的 Pipeline，还是重点在 OAM 的实现上？

KubeVela 和 OAM 是一体的，OAM 是 KubeVela 背后的模型，随着 KubeVela 的演进，OAM 模型也会随之迭代发展。

从最开始我们提出 OAM 模型，希望能够通过关注点分离的理念，降低云原生应用管理的复杂度，到后来出现 KubeVela 开箱即用的应用管理引擎，再到 v1.1 发布了混合云应用交付功能和工作流引擎。KubeVela 和 OAM 要解决的问题一直都是“让云原生的应用交付和应用管理更简单”。

为了让云原生应用交付和管理更简单，我们需要标准化的模型，以应用为中心降低用户使用门槛和心智负担，同时支持工作流、多集群等技术，也是为了让应用交付可以更流畅、更高效、成本更低。整个理念和发展方向都是一致的。

整体来说：Kubevela 正在向一款：原生面向混合云环境，以应用为中心的发布流水线一体化平台演进。

你可能偶尔会碰到如下问题。它发生在上一个 KubeVele 版本没有删除完成时。

稍事休息，然后在几秒内重试。


- Installing Vela Core Chart:
Vela system along with OAM runtime already exist.
Automatically discover capabilities successfully ✅ Add(0) Update(0) Delete(8)
TYPE        CATEGORY    DESCRIPTION
-task       workload    One-off task to run a piece of code or script to completion
-webservice workload    Long-running scalable service with stable endpoint to receive external traffic
-worker     workload    Long-running scalable backend worker without network endpoint
-autoscale  trait       Automatically scale the app following certain triggers or metrics
-metrics    trait       Configure metrics targets to be monitored for the app
-rollout    trait       Configure canary deployment strategy to release the app
-route      trait       Configure route policy to the app
-scaler     trait       Manually scale the app
- Finished successfully.

$ kubectl apply -f charts/vela-core/templates/defwithtemplate
traitdefinition.core.oam.dev/autoscale created
traitdefinition.core.oam.dev/scaler created
traitdefinition.core.oam.dev/metrics created
traitdefinition.core.oam.dev/rollout created
traitdefinition.core.oam.dev/route created
workloaddefinition.core.oam.dev/task created
workloaddefinition.core.oam.dev/webservice created
workloaddefinition.core.oam.dev/worker created
$ vela workloads
Automatically discover capabilities successfully ✅ Add(8) Update(0) Delete(0)
TYPE        CATEGORY    DESCRIPTION
+task       workload    One-off task to run a piece of code or script to completion
+webservice workload    Long-running scalable service with stable endpoint to receive external traffic
+worker     workload    Long-running scalable backend worker without network endpoint
+autoscale  trait       Automatically scale the app following certain triggers or metrics
+metrics    trait       Configure metrics targets to be monitored for the app
+rollout    trait       Configure canary deployment strategy to release the app
+route      trait       Configure route policy to the app
+scaler     trait       Manually scale the app
NAME        DESCRIPTION
task        One-off task to run a piece of code or script to completion
webservice  Long-running scalable service with stable endpoint to receive external traffic
worker      Long-running scalable backend worker without network endpoint

Error: ScopeDefinition exists

你可能偶尔会碰到如下问题。它发生在存在一个老的 OAM Kubernetes Runtime 发行版时，或者你之前已经部署过 ScopeDefinition 。

$ vela install
  - Installing Vela Core Chart:
  install chart vela-core, version 0.1.0, desc : A Helm chart for Kube Vela core, contains 35 file
  Failed to install the chart with error: ScopeDefinition "healthscopes.core.oam.dev" in namespace "" exists and cannot be imported into the current release: invalid ownership metadata; annotation validation error: key "meta.helm.sh/release-name" must equal "kubevela": current value is "oam"; annotation validation error: key "meta.helm.sh/release-namespace" must equal "vela-system": current value is "oam-system"
  rendered manifests contain a resource that already exists. Unable to continue with install
  helm.sh/helm/v3/pkg/action.(*Install).Run
    /home/runner/go/pkg/mod/helm.sh/helm/v3@v3.2.4/pkg/action/install.go:274
  ...
  Error: rendered manifests contain a resource that already exists. Unable to continue with install: ScopeDefinition "healthscopes.core.oam.dev" in namespace "" exists and cannot be imported into the current release: invalid ownership metadata; annotation validation error: key "meta.helm.sh/release-name" must equal "kubevela": current value is "oam"; annotation validation error: key "meta.helm.sh/release-namespace" must equal "vela-system": current value is "oam-system"

删除 ScopeDefinition “healthscopes.core.oam.dev” 然后重试.

You have reached your pull rate limit

当你查看 Pod kubevela-vela-core 的日志并发现如下问题时。

$ kubectl get pod -n vela-system -l app.kubernetes.io/name=vela-core
NAME                                 READY   STATUS    RESTARTS   AGE
kubevela-vela-core-f8b987775-wjg25   0/1     -         0          35m

你可以换成 github 的镜像仓库。

$ docker pull ghcr.io/oam-dev/kubevela/vela-core:latest

如果碰到以下问题，则可能存在一个 cert-manager 发行版，其 namespace 及 RBAC 相关资源与 KubeVela 存在冲突。

$ vela install
- Installing Vela Core Chart:
install chart vela-core, version 0.1.0, desc : A Helm chart for Kube Vela core, contains 35 file
Failed to install the chart with error: Namespace "cert-manager" in namespace "" exists and cannot be imported into the current release: invalid ownership metadata; label validation error: missing key "app.kubernetes.io/managed-by": must be set to "Helm"; annotation validation error: missing key "meta.helm.sh/release-name": must be set to "kubevela"; annotation validation error: missing key "meta.helm.sh/release-namespace": must be set to "vela-system"
rendered manifests contain a resource that already exists. Unable to continue with install
helm.sh/helm/v3/pkg/action.(*Install).Run
        /home/runner/go/pkg/mod/helm.sh/helm/v3@v3.2.4/pkg/action/install.go:274
...
        /opt/hostedtoolcache/go/1.14.12/x64/src/runtime/asm_amd64.s:1373
Error: rendered manifests contain a resource that already exists. Unable to continue with install: Namespace "cert-manager" in namespace "" exists and cannot be imported into the current release: invalid ownership metadata; label validation error: missing key "app.kubernetes.io/managed-by": must be set to "Helm"; annotation validation error: missing key "meta.helm.sh/release-name": must be set to "kubevela"; annotation validation error: missing key "meta.helm.sh/release-namespace": must be set to "vela-system"

尝试如下步骤修复这个问题。

删除 cert-manager 发行版
删除 cert-manager namespace

如何修复问题：MutatingWebhookConfiguration mutating-webhook-configuration exists?

如果你部署的其他服务会安装 MutatingWebhookConfiguration mutating-webhook-configuration，则安装 KubeVela 时会碰到如下问题。

- Installing Vela Core Chart:
install chart vela-core, version v0.2.1, desc : A Helm chart for Kube Vela core, contains 36 file
rendered manifests contain a resource that already exists. Unable to continue with install
helm.sh/helm/v3/pkg/action.(*Install).Run
    /home/runner/go/pkg/mod/helm.sh/helm/v3@v3.2.4/pkg/action/install.go:274
github.com/oam-dev/kubevela/pkg/commands.InstallOamRuntime
    /home/runner/work/kubevela/kubevela/pkg/commands/system.go:259
github.com/oam-dev/kubevela/pkg/commands.(*initCmd).run
    /home/runner/work/kubevela/kubevela/pkg/commands/system.go:162
github.com/oam-dev/kubevela/pkg/commands.NewInstallCommand.func2
    /home/runner/work/kubevela/kubevela/pkg/commands/system.go:119
github.com/spf13/cobra.(*Command).execute
    /home/runner/go/pkg/mod/github.com/spf13/cobra@v1.1.1/command.go:850
github.com/spf13/cobra.(*Command).ExecuteC
    /home/runner/go/pkg/mod/github.com/spf13/cobra@v1.1.1/command.go:958
github.com/spf13/cobra.(*Command).Execute
    /home/runner/go/pkg/mod/github.com/spf13/cobra@v1.1.1/command.go:895
main.main
    /home/runner/work/kubevela/kubevela/references/cmd/cli/main.go:16
runtime.main
    /opt/hostedtoolcache/go/1.14.13/x64/src/runtime/proc.go:203
runtime.goexit
    /opt/hostedtoolcache/go/1.14.13/x64/src/runtime/asm_amd64.s:1373
Error: rendered manifests contain a resource that already exists. Unable to continue with install: MutatingWebhookConfiguration "mutating-webhook-configuration" in namespace "" exists and cannot be imported into the current release: invalid ownership metadata; label validation error: missing key "app.kubernetes.io/managed-by": must be set to "Helm"; annotation validation error: missing key "meta.helm.sh/release-name": must be set to "kubevela"; annotation validation error: missing key "meta.helm.sh/release-namespace": must be set to "vela-system"

要解决这个问题，请从将 KubeVela Cli vela 版本升级到 v0.2.2 以上。

Autoscale: 如何在多个 Kubernetes 集群上开启 metrics server ？

运维 Autoscale 依赖 metrics server，所以它在许多集群中都是开启的。请通过命令 kubectl top nodes 或 kubectl top pods 检查 metrics server 是否开启。

$ kubectl top nodes
NAME                     CPU(cores)   CPU%   MEMORY(bytes)   MEMORY%
cn-hongkong.10.0.1.237   288m         7%     5378Mi          78%
cn-hongkong.10.0.1.238   351m         8%     5113Mi          74%
$ kubectl top pods
NAME                          CPU(cores)   MEMORY(bytes)
php-apache-65f444bf84-cjbs5   0m           1Mi
wordpress-55c59ccdd5-lf59d    1m           66Mi

或者需要在你的 kubernetes 集群中手动开启 metrics 。

ACK (Alibaba Cloud Container Service for Kubernetes)

Metrics server 已经开启。

ASK (Alibaba Cloud Serverless Kubernetes)

Metrics server 已经在如下 Operations/Add-ons 部分开启。

如果你有更多问题，请访问 metrics server 排错指导。

Kind

使用如下命令安装 metrics server，或者可以安装。

$ kubectl apply -f https://github.com/kubernetes-sigs/metrics-server/releases/download/v0.3.7/components.yaml

并且在通过 kubectl edit deploy -n kube-system metrics-server 加载的 yaml 文件中下增加如下部分。

注意：这里只是一个示例，而不是用于生产级别的使用。

MiniKube

使用如下命令开启。

享受在你的应用中设置 autoscale。