Node placement

Turn placement on when you want to keep OpenLM Platform on its own nodes, for example to separate it from other workloads, or to give the data-processing jobs nodes of their own.

By default, Kubernetes runs a pod on any node with room for it. That's fine for most installations, and it's what this guide sets up: placement is off.

How the chart does it

Every component belongs to one of two groups:

Group	Label value	What's in it
Services and UIs	main	Almost everything: about 100 components
Data processing	spark	The jobs that prepare reporting data: sparkmongo, sparkmssql, licenseconcurency, officetimecalculation, denialsaggregation and a few optional ones

With placement on, each pod requires a node with the label openlm.com/role set to its group, and tolerates a taint with the same key and value:

# what the chart adds to every pod when placement is on (component in group "main")
affinity:
  nodeAffinity:
    requiredDuringSchedulingIgnoredDuringExecution:
      nodeSelectorTerms:
        - matchExpressions:
            - { key: openlm.com/role, operator: In, values: [main] }
tolerations:
  - { key: openlm.com/role, operator: Equal, value: main, effect: NoSchedule }

The two switches are independent:

Setting	What it does
global.affinity.enabled: true	Pods run only on nodes labeled openlm.com/role=main (or =spark).
global.taints.enabled: true	Pods can run on nodes tainted openlm.com/role=main:NoSchedule (or spark). Other workloads are kept off those nodes by the taint.

The usual combination is both on: dedicated nodes that only OpenLM Platform uses.

Label the nodes before you turn affinity on

With global.affinity.enabled: true, a pod waits in Pending forever if no node carries its label. Label at least one node per group first. Both groups, main and spark, need nodes.

Turn placement on

To turn placement on:

1. Label (and, if you want exclusive nodes, taint) the nodes:

   kubectl label node <node> openlm.com/role=main
   kubectl taint node <node> openlm.com/role=main:NoSchedule      # optional: keep other pods off
   kubectl label node <spark-node> openlm.com/role=spark
   kubectl taint node <spark-node> openlm.com/role=spark:NoSchedule

   On managed clusters, set labels and taints on the node group or node pool instead, so new nodes get them automatically. See EKS and AKS.

2. Turn both switches on in openlm-values.yaml:

   global:
     affinity: { enabled: true }
     taints:   { enabled: true }

3. Apply the change with the same helm upgrade --install command as in step 6.

The label values are exactly main and spark

Values such as main-workload or reporting don't work. Node groups created from other templates often use different values. Check with kubectl get nodes -L openlm.com/role.

Your data services and placement

The placement settings apply only to the OpenLM Platform components. If you run MongoDB, Kafka or Redis inside the cluster, place them with their own charts' settings. The following table shows a common layout:

Node group	Label	Runs
Platform	openlm.com/role=main	OpenLM services and UIs, API gateway
Data processing	openlm.com/role=spark	Reporting data jobs
Infrastructure	your own label	MongoDB, Kafka, Redis, ingress controller

When you can't label nodes

On certain managed or shared clusters, for example a namespace on a shared OpenShift cluster, you don't have permission to label nodes. Leave both settings false. OpenLM Platform runs fine without placement.