linstor-scheduler

linstor-scheduler

Deploys a new Kubernetes scheduler, extended by the linstor-scheduler-extender.

The schedule is volume placement aware. That means that it prefers placing Pods on the same nodes as any Persistent Volume they might use. This works for any setup using LINSTOR, i.e. Piraeus Data-Store or LINBIT SDS.

Installation

The scheduler is meant to be installed in the same namespace as LINSTOR itself, otherwise additional steps may be required.

If installed along side Piraeus Operator, the LINSTOR endpoint is determined automatically. Otherwise, you need to set linstor.endpoint and linstor.clientSecret values as appropriate.

The following command will install the scheduler for a typical Piraeus Data-Store configuration with TLS enabled:

helm repo add piraeus-charts https://piraeus.io/helm-charts/
helm install linstor-scheduler piraeus-charts/linstor-scheduler --set linstorEndpoint=https://piraeus-op-cs.piraeus.svc:3371 --set linstorClientSecret=piraeus-client-secret

Usage

To use the scheduler, you need to configure it on your Pods (or Pod templates):

apiVersion: v1
kind: Pod
metadata:
  name: some-pod
spec:
  schedulerName: linstor-scheduler
  ...

Configuration

The following options are available:

Option	Usage	Default
replicaCount	Number of replicas to deploy.	1
linstor.endpoint	URL of the LINSTOR Controller API.	""
linstor.clientSecret	TLS secret to use to authenticate with the LINSTOR API	""
extender.image.repository	Repository to pull the linstor-scheduler-extender image from.	quay.io/piraeusdatastore/linstor-scheduler-extender
extender.image.pullPolicy	Pull policy to use. Possible values: IfNotPresent, Always, Never	IfNotPresent
extender.image.tag	Override the tag to pull. If not given, defaults to charts AppVersion.	""
extender.resources	Resources to request and limit on the container.	{}
extender.securityContext	Configure container security context. Defaults to dropping all capabilties and running as user 1000.	{capabilities: {drop: [ALL]}, readOnlyRootFilesystem: true, runAsNonRoot: true, runAsUser: 1000}
scheduler.image.repository	Repository to pull the kubernetes scheduler image from.	registry.k8s.io/kube-scheduler
scheduler.image.pullPolicy	Pull policy to use. Possible values: IfNotPresent, Always, Never	IfNotPresent
scheduler.image.tag	Override the tag to pull. If not given, defaults to kubernetes version.	""
scheduler.image.compatibleKubernetesRelease	Compatible kubernetes version for this scheduler, used to generate configuration in the right version.	""
scheduler.resources	Resources to request and limit on the container.	{}
scheduler.securityContext	Configure container security context. Defaults to dropping all capabilties and running as user 1000.	{capabilities: {drop: [ALL]}, readOnlyRootFilesystem: true, runAsNonRoot: true, runAsUser: 1000}
imagePullSecrets	Image pull secrets to add to the deployment.	[]
podAnnotations	Annotations to add to every pod in the deployment.	{}
podSecurityContext	Security context to set on the webhook pod.	{}
nodeSelector	Node selector to add to each webhook pod.	{}
tolerations	Tolerations to add to each webhook pod.	[]
affinity	Affinity to set on each webhook pod.	{}
rbac.create	Create the necessary roles and bindings for the snapshot controller.	true
serviceAccount.create	Create the service account resource	true
serviceAccount.name	Sets the name of the service account. If left empty, will use the release name as default	""
podDisruptionBudget.enabled	Enable creation of a pod disruption budget to protect the availability of the scheduler	true
autoscaling.enabled	Enable creation of a horizontal pod autoscaler to ensure availability in case of high usage`	"false