The easiest way to deploy YuniKorn is to leverage our helm charts, you can find the guide here. This document describes the manual process to deploy YuniKorn scheduler and it is majorly for developers.
Build docker image
Under project root of the
yunikorn-k8shim, run the command to build an image using the map for the configuration:
This command will build an image. The image will be tagged with a default version and image tag.
Note the default build uses a hardcoded user and tag. You must update the
IMAGE_TAG variable in the
Makefile to push to an appropriate repository.
The first step is to create the RBAC role for the scheduler, see yunikorn-rbac.yaml
The role is a requirement on the current versions of kubernetes.
Create the ConfigMap
This must be done before deploying the scheduler. It requires a correctly setup kubernetes environment. This kubernetes environment can be either local or remote.
- download configuration file if not available on the node to add to kubernetes:
- create ConfigMap in kubernetes:
- check if the ConfigMap was created correctly:
Note if name of the ConfigMap is changed the volume in the scheduler yaml file must be updated to reference the new name otherwise the changes to the configuration will not be picked up.
Attach ConfigMap to the Scheduler Pod
The ConfigMap is attached to the scheduler as a special volume. First step is to specify where to mount it in the pod:
Second step is to link the mount point back to the configuration map created in kubernetes:
Both steps are part of the scheduler yaml file, an example can be seen at scheduler.yaml for reference.
Deploy the Scheduler
The scheduler can be deployed with following command.
The deployment will run 2 containers from your pre-built docker images in 1 pod,
- yunikorn-scheduler-core (yunikorn scheduler core and shim for K8s)
- yunikorn-scheduler-web (web UI)
The pod is deployed as a customized scheduler, it will take the responsibility to schedule pods which explicitly specifies
schedulerName: yunikorn in pod's spec. In addition to the
schedulerName, you will also have to add a label
applicationId to the pod.
Note: Admission controller abstracts the addition of
applicationId from the user and hence, routes all traffic to YuniKorn. If you use helm chart to deploy, it will install admission controller along with the scheduler.
Access to the web UI
When the scheduler is deployed, the web UI is also deployed in a container. Port forwarding for the web interface on the standard ports can be turned on via:
9889 is the default port for Web UI,
9080 is the default port of scheduler's Restful service where web UI retrieves info from.
Once this is done, web UI will be available at: http://localhost:9889.
Configuration Hot Refresh
YuniKorn supports to load configuration changes automatically from attached configmap. Simply update the content in the configmap, that can be done either via Kubernetes dashboard UI or commandline. Note, changes made to the configmap might have some delay to be picked up by the scheduler.