k8s-scheduler-extender-example
This is an example of Kubernetes Scheduler Extender
How to
0. checkout the repo
$ git clone [email protected]:everpeace/k8s-scheduler-extender-example.git
$ cd k8s-scheduler-extender-example
$ git submodule update --init1. buid a docker image
$ IMAGE=YOUR_ORG/YOUR_IMAGE:YOUR_TAG
$ docker build . -t "${IMAGE}"
$ docker push "${IMAGE}"
2. deploy my-scheduler in kube-system namespace
please see ConfigMap in extender.yaml for scheduler policy json which includes scheduler extender config.
# bring up the kube-scheduler along with the extender image you've just built
$ sed 's/a\/b:c/'$(echo "${IMAGE}" | sed 's/\//\\\//')'/' extender.yaml | kubectl apply -f -
For ease of observation, start streaming logs from the extender:
$ kubectl -n kube-system logs deploy/my-scheduler -c my-scheduler-extender-ctr -f
[ warn ] 2018/11/07 08:41:40 main.go:84: LOG_LEVEL="" is empty or invalid, fallling back to "INFO".
[ info ] 2018/11/07 08:41:40 main.go:98: Log level was set to INFO
[ info ] 2018/11/07 08:41:40 main.go:116: server starting on the port :80Open up an another termianl and proceed.
3. schedule test pod
you will see test-pod will be scheduled by my-scheduler.
$ kubectl create -f test-pod.yaml
$ kubectl describe pod test-pod
Name: test-pod
...
Events:
Type Reason Age From Message
---- ------ ---- ---- -------
Normal Scheduled 25s my-scheduler Successfully assigned test-pod to minikube
Normal SuccessfulMountVolume 25s kubelet, minikube MountVolume.SetUp succeeded for volume "default-token-wrk5s"
Normal Pulling 24s kubelet, minikube pulling image "nginx"
Normal Pulled 8s kubelet, minikube Successfully pulled image "nginx"
Normal Created 8s kubelet, minikube Created container
Normal Started 8s kubelet, minikube Started container
License
Copyright 2018 Shingo Omura <https://github.com/everpeace>
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.