#Using Taints and Tolerations

You can use taints and tolerations to control which nodes the OpenTelemetry Collector pods are scheduled on. This is useful when you want to dedicate specific infrastructure nodes for observability workloads.

#Scheduling the Collector on infrastructure nodes

To schedule the OpenTelemetry Collector on infrastructure nodes, configure the nodeSelector and tolerations fields in the OpenTelemetryCollector custom resource.

Prerequisites

• The Alauda Build of OpenTelemetry v2 Operator must be installed.
• infrastructure nodes must be configured with the appropriate labels and taints.

Procedure

1. Verify that your infrastructure nodes are properly labeled and tainted:

   kubectl get nodes -l node-role.kubernetes.io/infra= -o custom-columns=NAME:.metadata.name,TAINTS:.spec.taints

2. Create or update the OpenTelemetryCollector resource with nodeSelector and tolerations:

   apiVersion: opentelemetry.io/v1beta1
   kind: OpenTelemetryCollector
   metadata:
     name: otel
     namespace: opentelemetry-collector
   spec:
     nodeSelector:
       node-role.kubernetes.io/infra: ""
     tolerations:
       - effect: NoSchedule
         key: node-role.kubernetes.io/infra
         value: reserved
         operator: Equal
     config:
       # ... collector config
   1. spec.nodeSelector: Constrains the Collector pods to only run on nodes matching the specified labels. In this example, nodes with the node-role.kubernetes.io/infra: "" label.
   2. spec.tolerations: Allows the Collector pods to be scheduled on nodes with matching taints. The NoSchedule effect prevents other pods without this toleration from being scheduled on these nodes.
   3. spec.tolerations[].operator: Set to Equal to require an exact match of the taint key and value.

Verification

Verify that the Collector pods are scheduled on the infrastructure nodes:

kubectl get pods -n opentelemetry-collector -o wide

Confirm that the NODE column shows the infrastructure node names.