Modern microservices-based architectures rely heavily on observability to ensure applications perform reliably at scale. This guide explains how to monitor Java applications on Kubernetes using Prometheus for metrics collection and Grafana for visualization, with hands-on steps, code examples, and best practices.<\/p>\n Kubernetes introduces dynamic scaling, service discovery, and container orchestration \u2014 which complicate monitoring. Traditional APM tools struggle with ephemeral pods and rolling updates.<\/p>\n Effective monitoring helps to:<\/strong><\/p>\n Detect performance bottlenecks.<\/p>\n<\/li>\n Identify memory leaks and GC pauses in JVMs.<\/p>\n<\/li>\n Track latency, throughput, and error rates.<\/p>\n<\/li>\n Visualize cluster-level resource consumption.<\/p>\n<\/li>\n<\/ul>\n Prometheus and Grafana simplify this by providing reliable time-series monitoring and dashboards that scale with your cluster.<\/p>\n Prometheus is a time-series database<\/strong> built for cloud-native monitoring. It scrapes metrics from endpoints and stores them efficiently.<\/p>\n Key Features:<\/strong><\/p>\n Pull-based data collection.<\/p>\n<\/li>\n Flexible PromQL query language.<\/p>\n<\/li>\n Built-in alerting with Alertmanager.<\/p>\n<\/li>\n Multi-dimensional data model.<\/p>\n<\/li>\n<\/ul>\n Grafana is an open-source analytics and visualization platform<\/strong> that integrates with Prometheus to present data in meaningful dashboards.<\/p>\n Key Features:<\/strong><\/p>\n Rich, interactive dashboards.<\/p>\n<\/li>\n Query editor with PromQL support.<\/p>\n<\/li>\n Alerts, annotations, and drill-downs.<\/p>\n<\/li>\n Multi-source and team access management.<\/p>\n<\/li>\n<\/ul>\n Kubernetes exposes performance data through its metrics APIs (via kube-state-metrics<\/strong> and cAdvisor<\/strong>). It enables Prometheus to dynamically discover and scrape metrics from Pods, Services, and Nodes.<\/p>\n Install Prometheus via Helm for simplicity:<\/p>\n Access Prometheus locally:<\/p>\n Visit: Expose metrics in your Java app using Micrometer<\/strong> (built into Spring Boot Actuator).<\/p>\n Add dependency:<\/strong><\/p>\n Enable Prometheus endpoint:<\/strong><\/p>\n Your metrics will now be available at:<\/p>\n Edit the Prometheus configuration to scrape your Java service:<\/p>\n Reload the Prometheus configuration, and it will start scraping your application\u2019s metrics automatically.<\/p>\n Install Grafana using Helm:<\/p>\n Expose the service:<\/p>\n Default credentials:<\/p>\n In Grafana \u2192 Settings \u2192 Data Sources<\/em>, add Prometheus with URL:<\/p>\n Import pre-made dashboards from the Grafana Dashboard Library
For Java<\/a> applications running on Kubernetes, Prometheus<\/strong> and Grafana<\/strong> are the standard tools for monitoring and visualization. Together, they offer a flexible system for collecting, storing, and analyzing metrics \u2014 allowing developers to detect issues before they affect end users.<\/p>\n
\nWhy Monitoring Matters in Kubernetes Environments<\/h2>\n
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\nCore Components<\/h2>\n
1. Prometheus<\/h3>\n
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2. Grafana<\/h3>\n
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3. Kubernetes<\/h3>\n
\nStep-by-Step Setup<\/h2>\n
Step 1: Deploy Prometheus on Kubernetes<\/h3>\n
helm repo add prometheus-community https:\/\/prometheus-community.github.io\/helm-charts\nhelm repo update\nhelm install prometheus prometheus-community\/prometheus\n<\/span><\/code><\/div>\n<\/div>\nkubectl port-forward deploy\/prometheus-server 9090:9090\n<\/span><\/code><\/div>\n<\/div>\nhttp:\/\/localhost:9090<\/code><\/p>\n
\nStep 2: Expose Java Application Metrics<\/h3>\n
<dependency<\/span><\/span>>\n <groupId<\/span><\/span>>io.micrometer<\/groupId<\/span><\/span>>\n <artifactId<\/span><\/span>>micrometer-registry-prometheus<\/artifactId<\/span><\/span>>\n<\/dependency<\/span><\/span>>\n<\/span><\/code><\/div>\n<\/div>\nmanagement:<\/span>\n endpoints:<\/span>\n web:<\/span>\n exposure:<\/span>\n include:<\/span> prometheus<\/span>\n<\/span><\/code><\/div>\n<\/div>\n\/actuator\/prometheus\n<\/span><\/code><\/div>\n<\/div>\n
\nStep 3: Configure Prometheus Scraping<\/h3>\n
scrape_configs:<\/span>\n -<\/span> job_name:<\/span> 'java-app'<\/span>\n metrics_path:<\/span> '\/actuator\/prometheus'<\/span>\n static_configs:<\/span>\n -<\/span> targets:<\/span> ['java-app-service.default.svc.cluster.local:8080'<\/span>]\n<\/span><\/code><\/div>\n<\/div>\n
\nStep 4: Deploy Grafana and Connect to Prometheus<\/h3>\n
helm install grafana grafana\/grafana\n<\/span><\/code><\/div>\n<\/div>\nkubectl port-forward svc\/grafana 3000:3000\n<\/span><\/code><\/div>\n<\/div>\nUsername: admin<\/span>\nPassword<\/span>: admin<\/span>\n<\/span><\/code><\/div>\n<\/div>\nhttp:\/\/prometheus-server:9090<\/span>\n<\/span><\/code><\/div>\n<\/div>\n
\nStep 5: Build Grafana Dashboards<\/h3>\n