Advanced Cluster Configurations

Advanced cluster configurations allow you to customize your NVIDIA Run:ai cluster deployment to support your environment. Some settings may be required for deployment, while others can be fine-tuned to align with organizational policies, security requirements, or other operational preferences.

By adjusting these configurations, you can influence system behavior, including functionality, scheduling policies, and resource management, giving you greater control over how the cluster operates. This article provides guidance on configuring and managing these settings so you can adapt your NVIDIA Run:ai cluster to your organization’s needs.

Configuration Scope

The Helm chart provides the complete set of configuration options for the NVIDIA Run:ai cluster. Some options, such as global.affinity, are available only through Helm. The rest of the configurable settings are grouped under clusterConfig. These clusterConfig settings can be applied through Helm as part of your deployment or upgrade process.

The clusterConfig subset can also be managed at runtime through the runaiconfig Custom Resource (under spec). For details, see Modify cluster configurations at runtime.

At runtime, runaiconfig is the source of truth for the active cluster configuration. If a configuration key is defined in both Helm and runaiconfig and the values differ, a Helm upgrade will overwrite the runaiconfig value to match the chart.

Note

The approach remains backward compatible so existing clusters configured via runaiconfig continue to work. However, when using Helm, you should manage configurations exclusively through Helm values. Mixing Helm values and manual runaiconfig edits is not recommended.

Helm Chart Values

The NVIDIA Run:ai cluster installation can be customized to support your environment via Helm values files or Helm install flags. For example:

# values.yaml
global:
  affinity:
    nodeAffinity:
      requiredDuringSchedulingIgnoredDuringExecution:
        nodeSelectorTerms:
          - matchExpressions:
              - key: node-role.kubernetes.io/runai-system
                operator: Exists

Modify Cluster Configurations at Runtime

The clusterConfig subset of settings can also be managed at runtime via the runaiconfig Kubernetes Custom Resource.

  1. To edit the cluster configurations, run:

    kubectl edit runaiconfig runai -n runai
  2. To see the full runaiconfig object structure, use:

    kubectl get crds/runaiconfigs.run.ai -n runai -o yaml

When using runaiconfig, the clusterConfig values appear under spec.

Configurations

The following configurations allow you to enable or disable features, control permissions, and customize the behavior of your NVIDIA Run:ai cluster

Note

  • Keys that start with clusterConfig are available both in Helm and at runtime in runaiconfig (under spec). All other keys are available only through Helm.

  • At runtime, runaiconfig reflects the active configuration. If specific clusterConfig values set in runaiconfig differ from those in Helm, a subsequent Helm upgrade will overwrite only those fields to align with the chart.

Key
Description

global.image.registry (string)

Global Docker image registry Default: ""

global.additionalImagePullSecrets (list)

List of image pull secrets references Default: []

global.affinity (object)

Sets the system nodes where NVIDIA Run:ai system-level services are scheduled. Using global.affinity will overwrite the node roles set using the Administrator CLI (runai-adm). Default: Prefer to schedule on nodes that are labeled with node-role.kubernetes.io/runai-system

global.tolerations (object)

Configure Kubernetes tolerations for NVIDIA Run:ai system-level services

global.additionalJobLabels (object)

Set NVIDIA Run:ai and 3rd party services' Pod Labels in a format of key/value pairs. Default: ""

global.additionalJobAnnotations (object)

Set NVIDIA Run:ai and 3rd party services' Annotations in a format of key/value pairs. Default: ""

global.customCA.enabled

Enables the use of a custom Certificate Authority (CA) in your deployment. When set to true, the system is configured to trust a user-provided CA certificate for secure communication.

global.customCAGit.enabled

Enables the use of a custom Certificate Authority (CA) for Git data sources. When set to true, the system uses the global CA certificate defined at installation unless overridden using global.customCAGit.secret.name.

global.customCAGit.secret.name

Specifies the name of the Kubernetes secret that contains a custom CA certificate for Git data sources. Overrides the default global CA when global.customCAGit.enabled is set to true.

global.customCAS3.enabled

Enables the use of a custom Certificate Authority (CA) for S3 data sources. When set to true, the system uses the global CA certificate defined at installation unless overridden using global.customS3Git.secret.name.

global.customCAS3.secret.name

Specifies the name of the Kubernetes secret that contains a custom CA certificate for S3 data sources. Overrides the default global CA when global.customCAS3.enabled is set to true.

openShift.securityContextConstraints.create

Enables the deployment of Security Context Constraints (SCC). Disable for CIS compliance. Default: true

researcherService.ingress.tlsSecret (string)

Existing secret key where cluster TLS certificates are stored (non-OpenShift) Default: runai-cluster-domain-tls-secret

researcherService.route.tlsSecret (string)

Existing secret key where cluster TLS certificates are stored (OpenShift only) Default: ""

clusterConfig.global.nodeAffinity.restrictScheduling (boolean)

Enables setting node roles and restricting workload scheduling to designated nodes Default: false

clusterConfig.global.subdomainSupport (boolean)

Allows the creation of subdomains for ingress endpoints, enabling access to workloads via unique subdomains on the Fully Qualified Domain Name (FQDN). For details, see External Access to Containers. Default: false

clusterConfig.global.devicePluginBindings (boolean)

Instruct NVIDIA Run:ai fractions to use device plugin for host mount instead of NVIDIA Run:ai fractions using explicit host path mount configuration on the pod. See GPU fractions and dynamic GPU fractions. Default: false

clusterConfig.global.enableWorkloadOwnershipProtection (boolean)

Prevents users within the same project from deleting workloads created by others. This enhances workload ownership security and ensures better collaboration by restricting unauthorized modifications or deletions. Default: false

clusterConfig.project-controller.createNamespaces (boolean)

Allows Kubernetes namespace creation for new projects Default: true

clusterConfig.project-controller.CreateRoleBindings (boolean)

Specifies if role bindings should be created in the project's namespace Default: true

clusterConfig.project-controller.limitRange (boolean)

Specifies if limit ranges should be defined for projects Default: true

clusterConfig.project-controller.clusterWideSecret (boolean)

Allows Kubernetes Secrets creation at the cluster scope. See Credentials for more details. Default: true

clusterConfig.workload-controller.failureResourceCleanupPolicy

NVIDIA Run:ai cleans the workload's unnecessary resources:

  • All - Removes all resources of the failed workload

  • None - Retains all resources

  • KeepFailing - Removes all resources except for those that encountered issues (primarily for debugging purposes)

Default: All

clusterConfig.workload-controller.GPUNetworkAccelerationEnabled

Enables GPU network acceleration. See Using GB200 NVL72 and Multi-Node NVLink Domains for more details. Default: false

clusterConfig.mps-server.enabled (boolean)

Enabled when using NVIDIA MPS Default: false

clusterConfig.daemonSetsTolerations (object)

Configure Kubernetes tolerations for NVIDIA Run:ai daemonSets / engine

clusterConfig.runai-container-toolkit.enabled (boolean)

Enables workloads to use GPU fractions Default: true

clusterConfig.runai-container-toolkit.logLevel (boolean)

Specifies the NVIDIA Run:ai-container-toolkit logging level: either 'SPAM', 'DEBUG', 'INFO', 'NOTICE', 'WARN', or 'ERROR' Default: INFO

clusterConfig.node-scale-adjuster.args.gpuMemoryToFractionRatio (object)

A scaling-pod requesting a single GPU device will be created for every 1 to 10 pods requesting fractional GPU memory (1/gpuMemoryToFractionRatio). This value represents the ratio (0.1-0.9) of fractional GPU memory (any size) to GPU fraction (portion) conversion. Default: 0.1

clusterConfig.global.core.dynamicFractions.enabled (boolean)

Enables dynamic GPU fractions Default: true

clusterConfig.global.core.swap.enabled (boolean)

Enables memory swap for GPU workloads Default: false

clusterConfig.global.core.swap.limits.cpuRam (string)

Sets the CPU memory size used to swap GPU workloads Default:100Gi

clusterConfig.global.core.swap.limits.reservedGpuRam (string)

Sets the reserved GPU memory size used to swap GPU workloads Default: 2Gi

clusterConfig.global.core.swap.biDirectional (string)

Sets the read/write memory mode of GPU memory swap to bi-directional (fully duplex). This produces higher performance (typically +80%) vs. uni-directional (simplex) read-write operations. For more details, see GPU memory swap. Default: false

clusterConfig.global.core.swap.mode (string)

Sets the GPU to CPU memory swap method to use UVA and optimized memory prefetch for optimized performance in some scenarios. For more details, see GPU memory swap. Default: None. The parameter is not set by default. To add this parameter set mode=mapped .

clusterConfig.global.core.nodeScheduler.enabled (boolean)

Enables the node-level scheduler Default: false

clusterConfig.global.core.timeSlicing.mode (string)

Sets the GPU time-slicing mode. Possible values:

  • timesharing - all pods on a GPU share the GPU compute time evenly.

  • strict - each pod gets an exact time slice according to its memory fraction value.

  • fair - each pod gets an exact time slice according to its memory fraction value and any unused GPU compute time is split evenly between the running pods.

Default: timesharing

clusterConfig.runai-scheduler.args.fullHierarchyFairness (boolean)

Enables fairness between departments, on top of projects fairness Default: true

clusterConfig.runai-scheduler.args.defaultStalenessGracePeriod

Sets the timeout in seconds before the scheduler evicts a stale pod-group (gang) that went below its min-members in running state:

  • 0s - Immediately (no timeout)

  • -1 - Never

Default: 60s

clusterConfig.runai-scheduler.args.verbosity (int)

Configures the level of detail in the logs generated by the scheduler service Default: 4

clusterConfig.pod-grouper.args.gangSchedulingKnative (boolean)

Enables gang scheduling for inference workloads.For backward compatibility with versions earlier than v2.19, change the value to false Default: false

clusterConfig.pod-grouper.args.gangScheduleArgoWorkflow (boolean)

Groups all pods of a single ArgoWorkflow workload into a single Pod-Group for gang scheduling Default: true

clusterConfig.limitRange.cpuDefaultRequestCpuLimitFactorNoGpu (string)

Sets a default ratio between the CPU request and the limit for workloads without GPU requests Default: 0.1

clusterConfig.limitRange.memoryDefaultRequestMemoryLimitFactorNoGpu (string)

Sets a default ratio between the memory request and the limit for workloads without GPU requests Default: 0.1

clusterConfig.limitRange.cpuDefaultRequestGpuFactor (string)

Sets a default amount of CPU allocated per GPU when the CPU is not specified Default: 100

clusterConfig.limitRange.cpuDefaultLimitGpuFactor (int)

Sets a default CPU limit based on the number of GPUs requested when no CPU limit is specified Default: NO DEFAULT

clusterConfig.limitRange.memoryDefaultRequestGpuFactor (string)

Sets a default amount of memory allocated per GPU when the memory is not specified Default: 100Mi

clusterConfig.limitRange.memoryDefaultLimitGpuFactor (string)

Sets a default memory limit based on the number of GPUs requested when no memory limit is specified Default: NO DEFAULT

NVIDIA Run:ai Services Resource Management

NVIDIA Run:ai cluster includes many different services. To simplify resource management, the configuration structure allows you to configure the containers CPU / memory resources for each service individually or group of services together.

Service Group
Description
NVIDIA Run:ai containers

SchedulingServices

Containers associated with the NVIDIA Run:ai Scheduler

Scheduler, StatusUpdater, MetricsExporter, PodGrouper, PodGroupAssigner, PodGroupController, QueueController, NodePoolController, Binder, DevicePlugin

SyncServices

Containers associated with syncing updates between the NVIDIA Run:ai cluster and the NVIDIA Run:ai control plane

Agent, ClusterSync, AssetsSync

WorkloadServices

Containers associated with submitting NVIDIA Run:ai workloads

WorkloadController, JobController, WorkloadOverseer, ExternalWorkloadIntegrator, ClusterRedis, ClusterAPI, InferenceWorkloadController, ResearcherService, SharedObjectsController, WorkloadExporter

Apply the following configuration in order to change resources request and limit for a group of services:

clusterConfig:
  global:
   <service-group-name>: # schedulingServices | SyncServices | WorkloadServices
     resources:
       limits:
         cpu: 1000m
         memory: 1Gi
       requests:
         cpu: 100m
         memory: 512Mi

Or, apply the following configuration in order to change resources request and limit for each service individually:

clusterConfig:
  <service-name>: # for example: pod-grouper
    resources:
      limits:
        cpu: 1000m
        memory: 1Gi
      requests:
        cpu: 100m
        memory: 512Mi

For resource recommendations, see Vertical scaling.

NVIDIA Run:ai Services Replicas

By default, all NVIDIA Run:ai containers are deployed with a single replica. Some services support multiple replicas for redundancy and performance.

To simplify configuring replicas, a global replicas configuration can be set and is applied to all supported services:

clusterConfig:
  global: 
    replicaCount: 1 # default

This can be overwritten for specific services (if supported). Services without the replicas configuration does not support replicas:

clusterConfig:
  <service-name>: # for example: pod-grouper
    replicas: 1 # default

Prometheus

The Prometheus instance in NVIDIA Run:ai is used for metrics collection and alerting.

The configuration scheme follows the official PrometheusSpec and supports additional custom configurations. The PrometheusSpec schema is available using the spec.prometheus.spec configuration.

A common use case using the PrometheusSpec is for metrics retention. This prevents metrics loss during potential connectivity issues and can be achieved by configuring local temporary metrics retention. For more information, see Prometheus Storage:

clusterConfig:  
  prometheus:
    spec: # PrometheusSpec
      retention: 2h # default 
      retentionSize: 20GB

In addition to the PrometheusSpec schema, some custom NVIDIA Run:ai configurations are also available:

  • Additional labels - Set additional labels for NVIDIA Run:ai's built-in alerts sent by Prometheus.

  • Log level configuration - Configure the logLevel setting for the Prometheus container.

  • Image override - Use prometheus.spec.image to manually specify the Prometheus image reference. Due to a known issue, the imageRegistry setting in the Prometheus Helm chart is ignored. To pull the image from a different registry, specify the full image reference. Default: quay.io/prometheus/prometheus.

  • Image pull secrets - Use prometheus.spec.imagePullSecrets to list Kubernetes image pull secrets in the runai namespace. This is particularly relevant for air-gapped installations where pulling Prometheus images requires authentication. Default: [].

clusterConfig:  
  prometheus:
    logLevel: info # debug | info | warn | error
    additionalAlertLabels:
      - env: prod # example

NVIDIA Run:ai Managed Nodes

To include or exclude specific nodes from running workloads within a cluster managed by NVIDIA Run:ai, use the nodeSelectorTerms flag. For additional details, see Kubernetes nodeSelector.

Label the nodes using the below:

  • key - Label key (e.g., zone, instance-type).

  • operator - Operator defining the inclusion/exclusion condition (In, NotIn, Exists, DoesNotExist).

  • values - List of values for the key when using In or NotIn.

The below example shows how to include NVIDIA GPUs only and exclude all other GPU types in a cluster with mixed nodes, based on product type GPU label:

clusterConfig:   
  global:
     managedNodes:
       inclusionCriteria:
          nodeSelectorTerms:
          - matchExpressions:
            - key: nvidia.com/gpu.product  
              operator: Exists

Custom Certificate Authority for Git and S3

To override the default global CA used by the system and inject a custom CA certificate for Git or S3 data sources, follow these steps:

  1. Create a Kubernetes secret with the custom CA certificate:

    kubectl -n runai create secret generic runai-cluster-git-ca \
        --from-file=runai-ca-git.pem=<ca_bundle_path>
    kubectl label secret runai-cluster-git-ca -n runai run.ai/cluster-wide=true run.ai/name=runai-ca-cert --overwrite
  2. When installing the cluster, make sure the following flags are added to the helm command. See Install cluster.

--set global.customCAGit.enabled=true \
--set global.customCAGit.secret.name=<secret-name>

Last updated