[scheduler] descheduler - 설치

Descheduler 는 Kubernetes 의 Scheduler 를 직접적으로 호출하지않고 CRD 방식으로 여러가지 k8s scheduler 에 관련된 동작을 수행하게 해주는 MIG Kubernetes 중 하나이다. 

 

설치는 아래와같은 여러가지 방식으로 가능하다.

 

[Manifest 로 직접 설치, rbac, configmap, workload 구성]

Run As A Job

kubectl create -f kubernetes/base/rbac.yaml
kubectl create -f kubernetes/base/configmap.yaml
kubectl create -f kubernetes/job/job.yaml

Run As A CronJob

kubectl create -f kubernetes/base/rbac.yaml
kubectl create -f kubernetes/base/configmap.yaml
kubectl create -f kubernetes/cronjob/cronjob.yaml

Run As A Deployment

kubectl create -f kubernetes/base/rbac.yaml
kubectl create -f kubernetes/base/configmap.yaml
kubectl create -f kubernetes/deployment/deployment.yaml

 

[Helm 설치]

 - helm repo 등록

helm repo add descheduler https://kubernetes-sigs.github.io/descheduler/
helm install my-release --namespace kube-system descheduler/descheduler

 - helm install 수행

helm install --namespace kube-system my-release descheduler/descheduler

 - helm delete 방식

helm delete my-release

 - helm 설치시 여러가지 Configuration

Parameter	Description	Default
kind	Use as CronJob or Deployment	CronJob
image.repository	Docker repository to use	k8s.gcr.io/descheduler/descheduler
image.tag	Docker tag to use	v[chart appVersion]
image.pullPolicy	Docker image pull policy	IfNotPresent
imagePullSecrets	Docker repository secrets	[]
nameOverride	String to partially override descheduler.fullname template (will prepend the release name)	""
fullnameOverride	String to fully override descheduler.fullname template	""
cronJobApiVersion	CronJob API Group Version	"batch/v1"
schedule	The cron schedule to run the descheduler job on	"*/2 * * * *"
startingDeadlineSeconds	If set, configure startingDeadlineSeconds for the descheduler job	nil
successfulJobsHistoryLimit	If set, configure successfulJobsHistoryLimit for the descheduler job	nil
failedJobsHistoryLimit	If set, configure failedJobsHistoryLimit for the descheduler job	nil
deschedulingInterval	If using kind:Deployment, sets time between consecutive descheduler executions.	5m
cmdOptions	The options to pass to the descheduler command	see values.yaml
deschedulerPolicy.strategies	The descheduler strategies to apply	see values.yaml
priorityClassName	The name of the priority class to add to pods	system-cluster-critical
rbac.create	If true, create & use RBAC resources	true
podSecurityPolicy.create	If true, create PodSecurityPolicy	true
resources	Descheduler container CPU and memory requests/limits	see values.yaml
serviceAccount.create	If true, create a service account for the cron job	true
serviceAccount.name	The name of the service account to use, if not set and create is true a name is generated using the fullname template	nil
serviceAccount.annotations	Specifies custom annotations for the serviceAccount	{}
nodeSelector	Node selectors to run the descheduler cronjob/deployment on specific nodes	nil
affinity	Node affinity to run the descheduler cronjob/deployment on specific nodes	nil
tolerations	tolerations to run the descheduler cronjob/deployment on specific nodes	nil
suspend	Set spec.suspend in descheduler cronjob	false
commonLabels	Labels to apply to all resources	{}
livenessProbe	Liveness probe configuration for the descheduler container	see values.yaml