Core DNS

Overview

CoreDNS provides internal DNS resolution for services and pods inside the Kubernetes cluster

Why it’s Useful

Tracks DNS query performance and failures.
Ensures service discovery works as expected.
Helps troubleshoot DNS latency that may affect workloads

What Users Can Do

Monitor DNS resolution times.
Verify query load across DNS pods.
Detect failed lookups early.

Steps to Modify Configuration

Get the existing ConfigMap.

kubectl get cm opsramp-k8s-infra-metric-user-config -n <agent-installed-namespace> -o yaml

Edit the ConfigMap:

kubectl edit cm opsramp-k8s-infra-metric-user-config -n <agent-installed-namespace>

Locate the coredns section in ConfigMap.

k8s_cluster:
  enabled: true
  config:
    scrape_interval: "2m"

Update the required parameters.
Save and apply the changes.

Supported Metrics

Metric Name	Display Name
coredns_build_info	coredns build info
coredns_cache_misses	coredns cache misses
coredns_cache_requests	coredns cache requests
coredns_dns_request_duration_seconds	coredns dns request duration seconds
coredns_dns_request_duration_seconds	coredns dns request duration seconds
coredns_dns_request_duration_seconds	coredns dns request duration seconds
coredns_dns_request_size_bytes	coredns dns request size bytes
coredns_dns_request_size_bytes	coredns dns request size bytes
coredns_dns_request_size_bytes	coredns dns request size bytes
coredns_dns_response_size_bytes	coredns dns response size bytes
coredns_dns_response_size_bytes	coredns dns response size bytes
coredns_dns_response_size_bytes	coredns dns response size bytes
coredns_dns_responses	coredns dns responses
coredns_forward_healthcheck_broken	coredns forward healthcheck broken
coredns_forward_max_concurrent_rejects	coredns forward max concurrent rejects
coredns_health_request_duration_seconds	coredns health request duration seconds
coredns_health_request_duration_seconds	coredns health request duration seconds
coredns_health_request_duration_seconds	coredns health request duration seconds
coredns_health_request_failures	coredns health request failures
coredns_hosts_reload_timestamp_seconds	coredns hosts reload timestamp seconds
coredns_kubernetes_dns_programming_duration_seconds	coredns kubernetes dns programming duration seconds
coredns_kubernetes_dns_programming_duration_seconds	coredns kubernetes dns programming duration seconds
coredns_kubernetes_dns_programming_duration_seconds	coredns kubernetes dns programming duration seconds
coredns_kubernetes_rest_client_rate_limiter_duration_seconds	coredns kubernetes rest client rate limiter duration seconds
coredns_kubernetes_rest_client_rate_limiter_duration_seconds	coredns kubernetes rest client rate limiter duration seconds
coredns_kubernetes_rest_client_rate_limiter_duration_seconds	coredns kubernetes rest client rate limiter duration seconds
coredns_kubernetes_rest_client_request_duration_seconds	coredns kubernetes rest client request duration seconds
coredns_kubernetes_rest_client_request_duration_seconds	coredns kubernetes rest client request duration seconds
coredns_kubernetes_rest_client_request_duration_seconds	coredns kubernetes rest client request duration seconds
coredns_kubernetes_rest_client_requests	coredns kubernetes rest client requests
coredns_local_localhost_requests	coredns local localhost requests
coredns_panics	coredns panics
coredns_plugin_enabled	coredns plugin enabled
coredns_proxy_conn_cache_hits	coredns proxy conn cache hits
coredns_proxy_conn_cache_misses	coredns proxy conn cache misses
coredns_proxy_request_duration_seconds	coredns proxy request duration seconds
coredns_proxy_request_duration_seconds	coredns proxy request duration seconds
coredns_proxy_request_duration_seconds	coredns proxy request duration seconds
coredns_reload_failed	coredns reload failed