Coverage Matrix
| Chkk Curated Release Notes | v0.8.2 to latest |
| Private Registry | Supported |
| Custom Built Images | Supported |
| Safety, Health, and Readiness Checks | v0.10.0 to latest |
| Supported Packages | Helm, Kustomize, Kube |
| EOL Information | Available |
| Version Incompatibility Information | Available |
| Upgrade Templates | In-Place, Blue-Green |
| Preverification | Available |
Prometheus Adapter Overview
Prometheus Adapter provides Kubernetes clusters with resource, custom, and external metrics APIs, enabling Horizontal Pod Autoscalers (HPAs) to leverage Prometheus-collected metrics beyond basic CPU and memory. By regularly querying Prometheus, the adapter exposes metrics through Kubernetes API endpoints (custom.metrics.k8s.io and external.metrics.k8s.io) for advanced autoscaling scenarios. Platform teams already using Prometheus can optionally replace Metrics Server entirely, streamlining metrics collection and reducing complexity. This integration unlocks highly granular, application-specific scaling policies directly driven by Prometheus data, significantly enhancing autoscaling effectiveness.
Chkk Coverage
Curated Release Notes
Chkk curates Prometheus Adapter release notes, highlighting only the most relevant changes for your environment, such as new metric discovery formats or required RBAC updates. It surfaces critical bug fixes, like query timeouts or certificate handling improvements, clarifying their operational impacts. If configuration syntax adjustments or API changes occur, Chkk explicitly calls out their significance to your deployment. This focused summary enables platform engineers to understand upgrade implications quickly and accurately, without sifting through irrelevant details.Preflight & Postflight Checks
Chkk’s preflight checks validate Kubernetes version compatibility, adapter configuration correctness, Prometheus connectivity, and RBAC permissions before upgrades. They proactively identify issues such as deprecated configuration syntax or unreachable Prometheus endpoints. After upgrading, postflight checks confirm the adapter’s operational health, API service availability, and HPA metric retrieval. Any issues, like failed metrics queries or adapter pod errors, are promptly flagged, ensuring quick resolution and minimal disruption.Version Recommendations
Chkk continuously monitors Prometheus Adapter versions, alerting teams when their deployment falls outside the community maintenance support window. By referencing release history and community feedback, Chkk highlights risks in older adapter versions, such as memory leaks or compatibility gaps. It suggests stable, tested upgrade targets aligned with Kubernetes versions and community best practices, balancing new features and proven stability. This approach ensures upgrades maintain operational reliability without introducing unforeseen problems.Upgrade Templates
Chkk provides structured Upgrade Templates for safe, repeatable Prometheus Adapter upgrades. Templates clearly document each step, including Helm or manifest updates, rollback instructions, and key checkpoints like API service availability validation. Though in-place upgrades are common, Chkk also supports blue-green testing with parallel adapter deployments in staging environments. Integrated seamlessly into GitOps and CI/CD workflows, these templates significantly reduce human error and enhance deployment confidence.Preverification
Chkk’s preverification simulates Prometheus Adapter upgrades in isolated environments, proactively surfacing configuration or compatibility issues like malformed queries or RBAC permission mismatches. By testing adapter deployments against representative Prometheus data, platform engineers can identify and resolve issues before production upgrades. Preverification provides detailed reports on adapter startup health, metric availability, query performance, and warnings. This “dry run” strategy ensures real upgrades proceed smoothly, minimizing risk and downtime.Supported Packages
Chkk supports diverse Prometheus Adapter deployment methods, including official Helm charts, Kustomize, static manifests, and packaged distributions like kube-prometheus. It fully respects custom images, private registries, or forks, ensuring precise upgrade recommendations tailored to your specific configuration. Chkk generates accurate manifests, Helm diffs, or Kustomize patches based on your existing management approach. Thus, teams maintain workflow consistency without modifying their established deployment practices.Common Operational Considerations
- Aggregated API Certificates: Misconfigured or invalid TLS certificates cause the API service to be unavailable, breaking metric collection. Automate certificate management (e.g., via cert-manager) to maintain valid certificates and avoid outages.
- Metrics Server Replacement: When using Prometheus Adapter to replace Metrics Server, ensure Prometheus scrapes core metrics (CPU/memory) and adapter rules expose them. Otherwise, HPAs relying on resource metrics may break unexpectedly.
- Misconfigured Metric Rules: Incorrect or overly broad PromQL queries in the adapter configuration lead to missing metrics or adapter startup failures. Validate queries externally first, and review adapter logs regularly to catch issues early.
- Multi-Tenant Isolation: The adapter’s global metrics exposure can cause cross-tenant metric leaks. Deploy separate adapter instances per tenant or enforce namespace-specific label filters within queries to maintain strict isolation.
- Query Load and Performance: Excessive or high-cardinality metric queries increase adapter and Prometheus resource usage, causing query delays or timeouts. Optimize PromQL queries, limit metric exposure, and monitor adapter resource utilization closely.
- HPA Scaling Issues: HPAs failing to scale typically indicate adapter configuration or metric availability issues. Verify metrics directly via Kubernetes API endpoints and closely monitor adapter health to ensure autoscaling remains reliable.