Yurtctl convert/revert

1.背景说明

由于 OpenYurt 对 Kubernetes 无侵入，所以 OpenYurt 提供了 Yurtctl convert/revert 命令，用于 Kubernetes 集群和 OpenYurt 集群的转换。该命令适用于测试环境，不推荐在生产环境中使用。

2.使用流程

2.1编译 Yurtctl

要快速构建和安装设置 yurtctl ，在编译系统已安装了 golang 1.13+ 和 bash 的前提下你可以执行以下命令来完成安装：

  1. ```sh
  2. $ git clone https://github.com/openyurtio/openyurt.git
  3. $ cd openyurt
  4. $ make build WHAT="yurtctl" ARCH="amd64" REGION=cn
  5. ```

生成的可执行文件将存放在 _output/bin/ 目录下。

2.2 Kubernetes To OpenYurt

在测试环境中，当用户已经拥有一个 Kubernetes 集群时，可以使用 Yurtctl convert 命令，快速地将集群转换为 OpenYurt 集群。目前，OpenYurt 支持 minkube、kind 以及手动搭建的 Kubernetes 集群的转换。

查看原生 Kubernetes 集群：

  1. $ kubectl get node
  2. NAME     STATUS   ROLES                  AGE   VERSION
  3. master   Ready    control-plane,master   24d   v1.20.0
  4. node1    Ready    <none>                 24d   v1.20.0
  5. node2    Ready    <none>                 24d   v1.20.0

使用 Yurtctl convert 命令进行集群转换。转换时，需要指定集群中的云端节点列表。

  1. $ _output/bin/yurtctl convert --provider ack --cloud-nodes master
  2. [preflight] Running pre-flight checks
  3. [preflight] Running node-servant-preflight-convert jobs to check on edge and cloud nodes. Job running may take a long time, and job failure will affect the execution of the next stage
  4. [runConvert] Label all nodes with edgeworker label, annotate all nodes with autonomy annotation
  5. [runConvert] Deploying yurt-controller-manager
  6. [runConvert] Running jobs for convert. Job running may take a long time, and job failure will not affect the execution of the next stage
  7. [runConvert] Running disable-node-controller jobs to disable node-controller
  8.     [INFO] servant job(yurtctl-disable-node-controller-master) has succeeded
  9. [runConvert] Running node-servant-convert jobs to deploy the yurt-hub and reset the kubelet service on edge and cloud nodes
  10.     [INFO] servant job(node-servant-convert-node1) has succeeded
  11.     [INFO] servant job(node-servant-convert-node2) has succeeded
  12.     [INFO] servant job(node-servant-convert-master) has succeeded
  13. [runConvert] If any job fails, you can get job information through 'kubectl get jobs -n kube-system' to debug.
  14.     Note that before the next conversion, please delete all related jobs so as not to affect the conversion.

转换完成之后，集群中会部署 yurt-controller-manager，yurt-hub 等组件。此外，边缘节点会自动开启节点自治功能。

在转换时 Yurtctl 提供了选项，用户可以选择设置 OpenYurt 集群的配置：

  1. --deploy-yurttunnel             是否部署 yurttunnel-server 以及 yurttunnel-agent
  2. --enable-app-manager            是否部署 yurt-app-manager
  3. --yurthub-image                                     yurthub 镜像
  4. --yurt-controller-manager-image     yurt-controller-manager 镜像
  5. --yurt-tunnel-server-image              yurttunnel-server 镜像
  6. --yurt-tunnel-agent-image                   yurttunnel-agent 镜像
  7. --yurt-app-manager-image                    yurt-app-manager-image 镜像

更多配置可以使用 yurtctl convert -h 获取。

注意：如果转换失败，请查询失败的 Job 的运行情况进行错误排查，并删除相关的 Job，以避免下一次转换发生错误。

2.3 OpenYurt To Kubernetes

OpenYurt 集群状况：

  1. $ kubectl get pod -A
  2. NAMESPACE     NAME                                       READY   STATUS    RESTARTS   AGE
  3. kube-system   coredns-54d67798b7-28r2s                   1/1     Running   0          24d
  4. kube-system   coredns-54d67798b7-wlmh8                   1/1     Running   0          24d
  5. kube-system   etcd-master                                1/1     Running   0          24d
  6. kube-system   kube-apiserver-master                      1/1     Running   0          24d
  7. kube-system   kube-controller-manager-master             1/1     Running   0          13d
  8. kube-system   kube-flannel-ds-4fmxr                      1/1     Running   0          24d
  9. kube-system   kube-flannel-ds-7r2fh                      1/1     Running   0          24d
  10. kube-system   kube-flannel-ds-j2xs5                      1/1     Running   0          24d
  11. kube-system   kube-proxy-6jh7s                           1/1     Running   0          24d
  12. kube-system   kube-proxy-9zdnz                           1/1     Running   0          24d
  13. kube-system   kube-proxy-trw2v                           1/1     Running   0          24d
  14. kube-system   kube-scheduler-master                      1/1     Running   0          24d
  15. kube-system   yurt-controller-manager-77b97fd47b-mhhxq   1/1     Running   0          13d
  16. kube-system   yurt-hub-master                            1/1     Running   0          13d
  17. kube-system   yurt-hub-node1                             1/1     Running   0          13d
  18. kube-system   yurt-hub-node2                             1/1     Running   0          13d

在测试环境中，通过执行以下命令将 OpenYurt 集群转换为 Kubernetes 集群：

  1. $ ./yurtctl revert
  2. I0107 11:36:25.694505    8473 revert.go:169] yurt controller manager is removed
  3. I0107 11:36:25.703390    8473 revert.go:178] serviceaccount for yurt controller manager is removed
  4. I0107 11:36:25.706450    8473 revert.go:187] clusterrole for yurt controller manager is removed
  5. I0107 11:36:25.709956    8473 revert.go:196] clusterrolebinding for yurt controller manager is removed
  6. I0107 11:36:25.720702    8473 revert.go:356] deployment for yurt app manager is removed
  7. I0107 11:36:25.721580    8473 revert.go:366] Role for yurt app manager is removed
  8. I0107 11:36:25.722411    8473 revert.go:375] ClusterRole for yurt app manager is removed
  9. I0107 11:36:25.723257    8473 revert.go:384] ClusterRoleBinding for yurt app manager is removed
  10. I0107 11:36:25.724132    8473 revert.go:394] RoleBinding for yurt app manager is removed
  11. I0107 11:36:25.870416    8473 revert.go:404] secret for yurt app manager is removed
  12. I0107 11:36:26.070564    8473 revert.go:414] Service for yurt app manager is removed
  13. I0107 11:36:26.071558    8473 revert.go:424] MutatingWebhookConfiguration for yurt app manager is removed
  14. I0107 11:36:26.072505    8473 revert.go:434] ValidatingWebhookConfiguration for yurt app manager is removed
  15. I0107 11:36:26.082843    8473 revert.go:443] crd for yurt app manager is removed
  16. I0107 11:36:26.092951    8473 revert.go:452] UnitedDeploymentcrd for yurt app manager is removed
  17. I0107 11:36:26.092968    8473 revert.go:212] yurt app manager is removed
  18.     [INFO] servant job(yurtctl-enable-node-controller-master) has succeeded
  19. I0107 11:36:56.118458    8473 revert.go:226] complete enabling node-controller
  20.     [INFO] servant job(node-servant-revert-node1) has succeeded
  21.     [INFO] servant job(node-servant-revert-node2) has succeeded
  22.     [INFO] servant job(node-servant-revert-master) has succeeded
  23. I0107 11:37:16.135272    8473 revert.go:239] complete removing yurt-hub and resetting kubelet service
  24. I0107 11:37:16.148484    8473 revert.go:246] delete yurthub clusterrole and clusterrolebinding
  25. I0107 11:37:16.155288    8473 revert.go:262] label openyurt.io/is-edge-worker is removed from node master
  26. I0107 11:37:16.155303    8473 revert.go:264] annotation node.beta.openyurt.io/autonomy is removed from node master
  27. I0107 11:37:16.159211    8473 revert.go:262] label openyurt.io/is-edge-worker is removed from node node1
  28. I0107 11:37:16.159229    8473 revert.go:264] annotation node.beta.openyurt.io/autonomy is removed from node node1
  29. I0107 11:37:16.163365    8473 revert.go:262] label openyurt.io/is-edge-worker is removed from node node2
  30. I0107 11:37:16.163384    8473 revert.go:264] annotation node.beta.openyurt.io/autonomy is removed from node node2

注意，在执行前需要确保所有边缘节点状态正常，以避免转换过程中发生错误。