Setup a MultiKueue environment

Additional steps needed to setup the multikueue clusters.

This tutorial explains how you can configure a management cluster and one worker cluster to run JobSets and batch/Jobs in a MultiKueue environment.

Check the concepts section for a MultiKueue overview.

Let’s assume that your manager cluster is named manager-cluster and your worker cluster is named worker1-cluster. To follow this tutorial, ensure that the credentials for all these clusters are present in the kubeconfig in your local machine. Check the kubectl documentation to learn more about how to Configure Access to Multiple Clusters.

In the Worker Cluster

When MultiKueue dispatches a workload from the manager cluster to a worker cluster, it expects that the job’s namespace and LocalQueue also exist in the worker cluster. In other words, you should ensure that the worker cluster configuration mirrors the one of the manager cluster in terms of namespaces and LocalQueues.

To create the sample queue setup in the default namespace, you can apply the following manifest:

apiVersion: kueue.x-k8s.io/v1beta1
kind: ResourceFlavor
metadata:
  name: "default-flavor"
---
apiVersion: kueue.x-k8s.io/v1beta1
kind: ClusterQueue
metadata:
  name: "cluster-queue"
spec:
  namespaceSelector: {} # match all.
  resourceGroups:
  - coveredResources: ["cpu", "memory"]
    flavors:
    - name: "default-flavor"
      resources:
      - name: "cpu"
        nominalQuota: 9
      - name: "memory"
        nominalQuota: 36Gi
---
apiVersion: kueue.x-k8s.io/v1beta1
kind: LocalQueue
metadata:
  namespace: "default"
  name: "user-queue"
spec:
  clusterQueue: "cluster-queue"

MultiKueue Specific Kubeconfig

In order to delegate the jobs in a worker cluster, the manager cluster needs to be able to create, delete, and watch workloads and their parent Jobs.

While kubectl is set up to use the worker cluster, download:

#!/bin/bash

# Copyright 2024 The Kubernetes Authors.
#
# 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.

set -o errexit
set -o nounset
set -o pipefail

KUBECONFIG_OUT=${1:-kubeconfig}
MULTIKUEUE_SA=multikueue-sa
NAMESPACE=kueue-system

# Creating a restricted MultiKueue role, service account and role binding"
kubectl apply -f - <<EOF
apiVersion: v1
kind: ServiceAccount
metadata:
  name: ${MULTIKUEUE_SA}
  namespace: ${NAMESPACE}
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRole
metadata:
  name: ${MULTIKUEUE_SA}-role
rules:
- apiGroups:
  - batch
  resources:
  - jobs
  verbs:
  - create
  - delete
  - get
  - list
  - watch
- apiGroups:
  - batch
  resources:
  - jobs/status
  verbs:
  - get
- apiGroups:
  - jobset.x-k8s.io
  resources:
  - jobsets
  verbs:
  - create
  - delete
  - get
  - list
  - watch
- apiGroups:
  - jobset.x-k8s.io
  resources:
  - jobsets/status
  verbs:
  - get
- apiGroups:
  - kueue.x-k8s.io
  resources:
  - workloads
  verbs:
  - create
  - delete
  - get
  - list
  - watch
- apiGroups:
  - kueue.x-k8s.io
  resources:
  - workloads/status
  verbs:
  - get
  - patch
  - update
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
  name: ${MULTIKUEUE_SA}-crb
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: ${MULTIKUEUE_SA}-role
subjects:
- kind: ServiceAccount
  name: ${MULTIKUEUE_SA}
  namespace: ${NAMESPACE}
EOF

# Get or create a secret bound to the new service account.
SA_SECRET_NAME=$(kubectl get -n ${NAMESPACE} sa/${MULTIKUEUE_SA} -o "jsonpath={.secrets[0]..name}")
if [ -z $SA_SECRET_NAME ]
then
kubectl apply -f - <<EOF
apiVersion: v1
kind: Secret
type: kubernetes.io/service-account-token
metadata:
  name: ${MULTIKUEUE_SA}
  namespace: ${NAMESPACE}
  annotations:
    kubernetes.io/service-account.name: "${MULTIKUEUE_SA}"
EOF

SA_SECRET_NAME=${MULTIKUEUE_SA}
fi

# Note: service account token is stored base64-encoded in the secret but must
# be plaintext in kubeconfig.
SA_TOKEN=$(kubectl get -n ${NAMESPACE} secrets/${SA_SECRET_NAME} -o "jsonpath={.data['token']}" | base64 -d)
CA_CERT=$(kubectl get -n ${NAMESPACE} secrets/${SA_SECRET_NAME} -o "jsonpath={.data['ca\.crt']}")

# Extract cluster IP from the current context
CURRENT_CONTEXT=$(kubectl config current-context)
CURRENT_CLUSTER=$(kubectl config view -o jsonpath="{.contexts[?(@.name == \"${CURRENT_CONTEXT}\"})].context.cluster}")
CURRENT_CLUSTER_ADDR=$(kubectl config view -o jsonpath="{.clusters[?(@.name == \"${CURRENT_CLUSTER}\"})].cluster.server}")

# Create the Kubeconfig file
echo "Writing kubeconfig in ${KUBECONFIG_OUT}"
cat > ${KUBECONFIG_OUT} <<EOF
apiVersion: v1
clusters:
- cluster:
    certificate-authority-data: ${CA_CERT}
    server: ${CURRENT_CLUSTER_ADDR}
  name: ${CURRENT_CLUSTER}
contexts:
- context:
    cluster: ${CURRENT_CLUSTER}
    user: ${CURRENT_CLUSTER}-${MULTIKUEUE_SA}
  name: ${CURRENT_CONTEXT}
current-context: ${CURRENT_CONTEXT}
kind: Config
preferences: {}
users:
- name: ${CURRENT_CLUSTER}-${MULTIKUEUE_SA}
  user:
    token: ${SA_TOKEN}
EOF

And run:

chmod +x create-multikueue-kubeconfig.sh
./create-multikueue-kubeconfig.sh worker1.kubeconfig

To create a Kubeconfig that can be used in the manager cluster to delegate Jobs in the current worker.

In the Manager Cluster

JobSet installation

If you are using Kueue in version 0.7.0 or newer install the JobSet on the management cluster (see JobSet Installation for more details). Please install JobSet 0.5.1 or newer for MultiKueue.

Enable the MultiKueue feature

Enable the MultiKueue feature. Check the Installation guide for details on feature gate configuration.

Create worker’s Kubeconfig secret

For the next example, having the worker1 cluster Kubeconfig stored in a file called worker1.kubeconfig, you can create the worker1-secret secret by running the following command:

 kubectl create secret generic worker1-secret -n kueue-system --from-file=kubeconfig=worker1.kubeconfig

Check the worker section for details on Kubeconfig generation.

Create a sample setup

Apply the following to create a sample setup in which the Jobs submitted in the ClusterQueue cluster-queue are delegated to a worker worker1

apiVersion: kueue.x-k8s.io/v1beta1
kind: ResourceFlavor
metadata:
  name: "default-flavor"
---
apiVersion: kueue.x-k8s.io/v1beta1
kind: ClusterQueue
metadata:
  name: "cluster-queue"
spec:
  namespaceSelector: {} # match all.
  resourceGroups:
  - coveredResources: ["cpu", "memory"]
    flavors:
    - name: "default-flavor"
      resources:
      - name: "cpu"
        nominalQuota: 9
      - name: "memory"
        nominalQuota: 36Gi
  admissionChecks:
  - sample-multikueue
---
apiVersion: kueue.x-k8s.io/v1beta1
kind: LocalQueue
metadata:
  namespace: "default"
  name: "user-queue"
spec:
  clusterQueue: "cluster-queue"
---
apiVersion: kueue.x-k8s.io/v1beta1
kind: AdmissionCheck
metadata:
  name: sample-multikueue
spec:
  controllerName: kueue.x-k8s.io/multikueue
  parameters:
    apiGroup: kueue.x-k8s.io
    kind: MultiKueueConfig
    name: multikueue-test
---
apiVersion: kueue.x-k8s.io/v1alpha1
kind: MultiKueueConfig
metadata:
  name: multikueue-test
spec:
  clusters:
  - multikueue-test-worker1
---
apiVersion: kueue.x-k8s.io/v1alpha1
kind: MultiKueueCluster
metadata:
  name: multikueue-test-worker1
spec:
  kubeConfig:
    locationType: Secret
    location: worker1-secret
    # a secret called "worker1-secret" should be created in the namespace the kueue
    # controller manager runs into, holding the kubeConfig needed to connect to the
    # worker cluster in the "kubeconfig" key;

Upon successful configuration the created ClusterQueue, AdmissionCheck and MultiKueueCluster will become active.

Run:

kubectl get clusterqueues cluster-queue -o jsonpath="{range .status.conditions[?(@.type == \"Active\")]}CQ - Active: {@.status} Reason: {@.reason} Message: {@.message}{'\n'}{end}"
kubectl get admissionchecks sample-multikueue -o jsonpath="{range .status.conditions[?(@.type == \"Active\")]}AC - Active: {@.status} Reason: {@.reason} Message: {@.message}{'\n'}{end}"
kubectl get multikueuecluster multikueue-test-worker1 -o jsonpath="{range .status.conditions[?(@.type == \"Active\")]}MC - Active: {@.status} Reason: {@.reason} Message: {@.message}{'\n'}{end}"

And expect an output like:

CQ - Active: True Reason: Ready Message: Can admit new workloads
AC - Active: True Reason: Active Message: The admission check is active
MC - Active: True Reason: Active Message: Connected

Last modified August 7, 2024: Fixed site notes color. (#2788) (fa3bb391)