• This project is used for pod migration between different nodes. It utilize the CRIU(checpoint-restore in userspace) linux kernel module to keep the state of the running container, and then recreate a new pod with wrapping the checkpoint state on the new node. Therefore, the new pod could be successfully restored.

1. MigrationController: it's used for monitoring the change of the state of CR(custom resoure). When the state of CR changes, then the controller will do the ongoing processes, like creating the corresponding client with given the certificate in /etc/kubernetes/pki folder in master node to enable the controller to access the kubelet checkpoint api which is located at https://"workernode-ip"+10250. The full command to access the kubelet api endpoint is curl -X POST "https://localhost:10250/checkpoint/namespace/"podId"/"ContainerName"
2. DaemonSetController: It is for monitoring the private docker registry pod deployed on each node to examine whether the checkpointed image has been pushed to the registry pod which is located at the destination node. I deploy a Strimzi, kafka broker service deployed on Kubernetes on the cluster. When the checkpointed image pushed to the registry pod, the webhook of the registry will be sent to the event handler deployed as a pod on the same node as docker private registry pod. Then that handler will create a kafka message then send it to the kafka service broker to let the controller to receive. Finally the controller will create a new pod with the checkpointed image on the registry pod on the destination node.

• make docker-build docker-push
• make manifests
• make install
• make deploy

• go version 1.22.4
• docker version 24.0.5
• kubectl version v1.28.9+.
• Access to a Kubernetes v1.28.9+ cluster.

Notes the checkpoint restore funcationality only supports the kubernetes v1.25.0+ version

Build and push your image to the location specified by IMG:

make docker-build docker-push IMG=<some-registry>/practice:tag

NOTE: This image ought to be published in the personal registry you specified. And it is required to have access to pull the image from the working environment. Make sure you have the proper permission to the registry if the above commands don’t work.

Install the CRDs into the cluster:

make install

Deploy the Manager to the cluster with the image specified by IMG:

make deploy IMG=<some-registry>/practice:tag

NOTE: After using make deploy command, then type this command on your master node: kubectl -n practice-system create secret generic kubelet-client-certs --from-file=client.crt=/etc/kubernetes/pki/apiserver-kubelet-client.crt --from-file=client.key=/etc/kubernetes/pki/apiserver-kubelet-client.key --kubeconfig=/home/ubuntu/.kube/config

NOTE: If you encounter RBAC errors, you may need to grant yourself cluster-admin privileges or be logged in as admin.

Create instances of your solution You can apply the samples (examples) from the config/sample:

kubectl apply -k config/samples/
kubectl apply -f config/samples/api_v1alpha1_migration.yaml

NOTE: Ensure that the samples has default values to test it out.

Delete the instances (CRs) from the cluster:

kubectl delete -k config/samples/

Delete the APIs(CRDs) from the cluster:

make uninstall

UnDeploy the controller from the cluster:

make undeploy

kubectl create secret docker-registry regcred
--docker-server="https://index.docker.io/v1/"
--docker-username=""
--docker-password=""
--docker-email=""

AccessToken: you can create this from the docker hub in the security tab

Following are the steps to build the installer and distribute this project to users.

1. Build the installer for the image built and published in the registry:

make build-installer IMG=<some-registry>/practice:tag

NOTE: The makefile target mentioned above generates an 'install.yaml' file in the dist directory. This file contains all the resources built with Kustomize, which are necessary to install this project without its dependencies.

2. Using the installer

Users can just run kubectl apply -f to install the project, i.e.:

kubectl apply -f https://raw.githubusercontent.com/<org>/practice/<tag or branch>/dist/install.yaml

// TODO(user): Add detailed information on how you would like others to contribute to this project

NOTE: Run make help for more information on all potential make targets

More information can be found via the Kubebuilder Documentation

Copyright 2024.

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.