How to Monitor Kubernetes Cluster? - OpsNexa

How to Monitor Kubernetes Cluster – The Complete Guide by OpsNexa

Monitoring a Kubernetes cluster is a critical part of maintaining a stable and high-performing infrastructure. With so many moving parts—containers, pods, nodes, services, and the control plane—Kubernetes monitoring provides the visibility needed to keep applications healthy and scalable. At OpsNexa, we help teams deploy monitoring stacks that capture the right data and enable faster incident response. This guide walks you through what to monitor, which tools to use, and how to design a sustainable observability system for your Kubernetes workloads.

Why Monitoring Kubernetes Matters More Than Ever

Kubernetes introduces abstraction and automation, which are excellent for scaling but dangerous when not observed closely. A failing pod, an unresponsive node, or an overwhelmed API server can bring down your workloads without warning. That’s why you need to monitor:

• Cluster health (nodes, system components)

• Pod and container performance

• Custom application metrics

• Logging and tracing

• Storage and networking

• Autoscaling behavior and thresholds

Without real-time monitoring, troubleshooting becomes a guessing game. Monitoring isn’t just about reacting to issues; it enables capacity planning, performance optimization, and proactive alerting. At OpsNexa, we’ve seen businesses cut MTTR in half simply by integrating proper cluster visibility.

What You Should Monitor in a Kubernetes Cluster

To truly understand what’s happening in your cluster, you need to monitor key resource types and signals. Here are the primary targets:

Cluster-Level Metrics:

• Node CPU/memory usage

• Node disk I/O and network throughput

• Node availability and readiness

Pod-Level Metrics:

• Pod uptime and restarts

• CPU/memory usage per container

• Liveness and readiness probe failures

Control Plane Components:

• API server response times

• etcd health and size

• Scheduler latency

Application Metrics:

• Custom business KPIs

• Response time, error rate, request throughput (RED method)

• Metrics exported via /metrics using Prometheus clients

Network and Storage:

• Ingress controller stats

• Persistent volume usage and I/O performance

Monitoring these data points ensures visibility from infrastructure to application layer. OpsNexa recommends setting monitoring baselines for each category and defining alert thresholds using historical patterns.

Best Tools to Monitor Kubernetes Clusters

Many open-source and cloud-native tools are available to monitor Kubernetes. The most popular and battle-tested stack is Prometheus + Grafana, but depending on your needs, you may expand the stack or integrate with cloud tools.

Prometheus:

• Scrapes metrics from Kubernetes endpoints

• Stores them in a time-series database

• Ideal for alerting and high-dimensional monitoring

Grafana:

• Visualizes metrics via dashboards

• Offers alerting with thresholds

• Supports Prometheus, Loki, Elasticsearch, and more

kube-state-metrics:

• Provides resource-level cluster information

• Useful for deployments, daemonsets, nodes, and namespaces

Alertmanager:

• Sends alerts triggered by Prometheus

• Supports routing to email, Slack, PagerDuty, etc.

Loki:

• Lightweight, scalable logging solution

• Pairs well with Grafana for logs + metrics dashboards

Jaeger or OpenTelemetry:

• Distributed tracing for microservices

• Tracks request flow across services and APIs

At OpsNexa, we often deploy preconfigured observability stacks using Helm and customize them with GitOps for automated updates.

How to Set Up Prometheus and Grafana on Kubernetes

Here’s how to quickly deploy a full-featured monitoring stack using Helm:

1. Install Helm (if not already installed):

2. Add the Prometheus Helm repository:

3. Deploy Prometheus and Grafana:

This setup includes Prometheus, Alertmanager, Grafana, and default dashboards for nodes, pods, and workloads.

4. Access the Grafana dashboard:

Then go to http://localhost:3000. Default credentials are admin/admin.

From there, import Kubernetes dashboards and set up alerts based on Prometheus queries like:

We at OpsNexa encourage clients to deploy monitoring as code with Helm values files and Git-backed repositories, improving reproducibility and auditability.

OpsNexa’s Best Practices for Kubernetes Monitoring

Monitoring is more than installing tools—it’s about strategy, governance, and actionability. Here are OpsNexa’s expert practices to ensure your observability stack performs at scale:

1. Use Labels and Namespaces Wisely

Group metrics and dashboards by teams, environments, or services using Kubernetes labels. This helps create scoped views in Grafana and limits alert noise.

2. Define SLIs and SLOs

Don’t drown in data. Track meaningful indicators like request latency or error rates and tie them to service level objectives (SLOs) that your team commits to maintaining.

3. Monitor the Monitor

Set up heartbeat checks for Prometheus, Alertmanager, and Grafana. If your monitoring system fails, you’ll lose observability exactly when you need it.

4. Avoid High-Cardinality Pitfalls

Overuse of labels (like user IDs) can overload Prometheus. Use aggregation and metric filtering to keep cardinality in check.

5. Integrate Logs, Metrics, and Traces

Combine metrics from Prometheus, logs from Loki, and traces from OpenTelemetry for full-context observability in Grafana.

6. Automate with CI/CD

Deploy monitoring resources (dashboards, alerts, configurations) using GitOps tools like ArgoCD or Flux. This reduces manual errors and maintains compliance.

At OpsNexa, our clients benefit from automated alert testing, templated dashboards, and self-healing monitors—all tailored to their workloads and scale.

Conclusion: Monitor Kubernetes Clusters the Smart Way with OpsNexa

Monitoring Kubernetes effectively is key to running stable, scalable, and secure applications. From setting up Prometheus and Grafana to defining custom alerts and SLOs, observability is no longer optional—it’s essential.

Whether you’re operating a few clusters or managing a multi-tenant platform, OpsNexa helps you build a resilient monitoring stack tailored to your environment. Our Kubernetes experts offer consulting, implementation, and ongoing support so you can focus on delivering value while we handle your visibility.

Need help setting up or optimizing your Kubernetes observability? Contact OpsNexa today for expert guidance and customized solutions.