Introduction to DNS Observability Challenges

DNS plays a vital role in Kubernetes service discovery, enabling pods to locate and communicate with other services within the cluster seamlessly. It also facilitates external connectivity, resolving domain names of services outside the cluster to their appropriate IP addresses. Kubernetes uses CoreDNS pods exposed via the kube-dns service, automatically configuring pod-level DNS resolvers to forward queries to this service.

DNS Observability Challenges in Kubernetes

• DNS issues can severely affect application performance and reliability in Kubernetes, often stemming from misconfigurations, service failures, or underlying infrastructure bottlenecks.

• Common symptoms of DNS problems include increased latency, transaction timeouts, and degraded user experience, making root cause analysis difficult.

• Kubernetes relies on upstream DNS servers for external name resolution, introducing dependencies that can impact the entire cluster if those servers experience issues.

• DNS queries may pass through multiple servers and involve recursive lookups, increasing the risk of delays and failures along the resolution path.

• Robust DNS observability is essential for diagnosing complex issues and maintaining application stability within Kubernetes environments.