Oracle Cloud Infrastructure Documentation

CoreDNS

When you enable the CoreDNS cluster add-on, you can pass the following key/value pairs as arguments.

Configuration Arguments Common to all Cluster Add-ons
Key (API and CLI) Key's Display Name (Console) Description Required/Optional Default Value Example Value
affinity affinity

A group of affinity scheduling rules.

JSON format in plain text or Base64 encoded.

 Optional null null
nodeSelectors node selectors

You can use node selectors and node labels to control the worker nodes on which add-on pods run.

For a pod to run on a node, the pod's node selector must have the same key/value as the node's label.

Set nodeSelectors to a key/value pair that matches both the pod's node selector, and the worker node's label.

JSON format in plain text or Base64 encoded.

 Optional null {"foo":"bar", "foo2": "bar2"}

The pod will only run on nodes that have the foo=bar or foo2=bar2 label.
numOfReplicas numOfReplicas The number of replicas of the add-on deployment.

(For CoreDNS, use nodesPerReplica instead.)

 Required 1

Creates one replica of the add-on deployment per cluster.

 2

Creates two replicas of the add-on deployment per cluster.
rollingUpdate rollingUpdate

Controls the desired behavior of rolling update by maxSurge and maxUnavailable.

JSON format in plain text or Base64 encoded.

 Optional null null
tolerations tolerations

You can use taints and tolerations to control the worker nodes on which add-on pods run.

For a pod to run on a node that has a taint, the pod must have a corresponding toleration.

Set tolerations to a key/value pair that matches both the pod's toleration, and the worker node's taint.

JSON format in plain text or Base64 encoded.

 Optional null [{"key":"tolerationKeyFoo", "value":"tolerationValBar", "effect":"noSchedule", "operator":"exists"}]

Only pods that have this toleration can run on worker nodes that have the tolerationKeyFoo=tolerationValBar:noSchedule taint.
topologySpreadConstraints topologySpreadConstraints

How to spread matching pods among the given topology.

JSON format in plain text or Base64 encoded.

 Optional null null
Configuration Arguments Specific to this Cluster Add-on
Key (API and CLI) Key's Display Name (Console) Description Required/Optional Default Value Example Value
coreDnsContainerResources CoreDNS container resources

You can specify the resource quantities that the add-on containers request, and set resource usage limits that the add-on containers cannot exceed.

JSON format in plain text or Base64 encoded.

 Optional null {"limits": {"cpu": "500m", "memory": "200Mi" }, "requests": {"cpu": "100m", "memory": "100Mi"}}

Create add-on containers that request 100 milllicores of CPU, and 100 mebibytes of memory. Limit add-on containers to 500 milllicores of CPU, and 200 mebibytes of memory.
corednsEnhancedMetrics CoreDNS enhanced metrics

The granularity of CoreDNS metrics to generate.

If you want CoreDNS to generate default metrics, set corednsEnhancedMetrics to false. If you want CoreDNS to generate more granular metrics for Kubernetes and OCI internal network traffic, set corednsEnhancedMetrics to true.

Note that the default value of corednsEnhancedMetrics depends on the version of Kubernetes that the cluster is running.

 Optional true for clusters running Kubernetes version 1.34.1 and later.

false for clusters running Kubernetes version 1.34.0 and earlier.

 true
customizeCoreDNSConfigMap customize CoreDNS configMap

If you want Oracle to manage CoreDNS for you automatically, set customizeCoreDNSConfigMap to false (the default).

If you want to customize CoreDNS behavior, set customizeCoreDNSConfigMap to true and create a coredns configMap in the kube-system namespace.

 Required false true
minReplica min replica

The minimum number of replicas of the CoreDNS deployment.

 Required 1

Creates a total of one pod in the cluster.

 2

Creates a total of two pods in the cluster.
nodesPerReplica nodes per replica

The number of CoreDNS replicas per cluster node.

 Required 1

Creates a replica on every node.

 2

Creates a replica on every second node.