Application Services
Knative Serving
Chkk coverage for Knative Serving. We provide version recommendations, preflight/postflight checks, and Upgrade Templates—ensuring worry-free operations.
Coverage Matrix
| Chkk Curated Release Notes | v0.23.2 to latest |
| Private Registry | Supported |
| Custom Built Images | Supported |
| Safety, Health, and Readiness Checks | v1.2.5 to latest |
| Supported Packages | Helm, Kustomize, Kube |
| EOL Information | Available |
| Version Incompatibility Information | Available |
| Upgrade Templates | In-Place, Blue-Green |
| Preverification | Available |
Knative Serving Overview
Knative Serving is a Kubernetes-native serverless platform that simplifies containerized application deployments using custom resources like Service, Route, Configuration, and Revision. It automates network routing, dynamic autoscaling—including scale-to-zero—and revision-based deployments, enabling blue-green or canary rollouts effortlessly. Knative integrates seamlessly with ingress controllers such as Istio, Kourier, and Contour, allowing platform engineers to leverage existing networking infrastructure. Each application change generates an immutable Revision object, facilitating precise version tracking and traffic management without manual Kubernetes intervention.Chkk Coverage
Curated Release Notes
Chkk curates Knative Serving release notes, highlighting new features, breaking changes, or deprecated APIs specifically relevant to your clusters. Instead of parsing exhaustive upstream notes, engineers receive concise summaries of impactful changes, such as the removal of older API versions or modifications to default behaviors. If an update introduces autoscaling algorithm adjustments or config-map changes, Chkk explicitly flags these details. This targeted curation helps you proactively adapt configurations and prevents unexpected operational disruptions.Preflight & Postflight Checks
Chkk performs preflight checks to ensure your cluster’s Kubernetes version, Knative CRDs, and configurations meet upgrade prerequisites, preventing common pitfalls such as version mismatches or deprecated field usage. It enforces sequential upgrades, avoiding unpredictable behavior from skipped minor versions. After upgrading, postflight checks validate Knative component health (e.g., controllers, activator) and readiness status of user services. Any anomalies, like revisions failing readiness or traffic routing issues, are immediately flagged, reducing downtime and operational risk.Version Recommendations
Chkk continuously monitors Knative Serving versions, clearly recommending stable, supported upgrades aligned with community feedback and compatibility with your Kubernetes clusters. It warns proactively when your current version approaches end-of-life or misses critical security patches. By aligning recommendations with Knative’s official support matrix and known issues, Chkk helps platform engineers balance adopting new features against operational stability. This prevents security vulnerabilities and compatibility problems from impacting production deployments.Upgrade Templates
Chkk provides structured Upgrade Templates supporting both in-place and blue-green upgrade methods. Templates include step-by-step guidance on applying Knative Serving manifests, sequencing CRD updates, and controlled pod restarts to minimize downtime. For higher-risk environments, Chkk outlines blue-green approaches, such as deploying a parallel Knative setup for phased traffic shifting and rollback safety. Clearly defined rollback points and best practices from official Knative documentation reduce the complexity and risk of manual upgrades.Preverification
Chkk’s Preverification feature simulates Knative Serving upgrades in isolated environments before applying them in production. This process identifies issues such as incompatible fields, CRD conflicts, or autoscaling anomalies. By running test traffic and configuration checks against a representative cluster, preverification uncovers issues like deprecated annotations or performance regressions early. This practice significantly improves upgrade reliability, allowing platform teams to confidently execute production upgrades.Supported Packages
Chkk supports Knative Serving deployments across multiple installation methods including YAML manifests, the Knative Operator, and Helm charts. It intelligently adapts upgrade guidance based on your chosen packaging method, accommodating vendor-specific builds and private registries. Chkk integrates with existing GitOps workflows, preserving consistency in image versions and custom configurations. This flexibility ensures upgrade recommendations remain relevant regardless of your deployment practices.Common Operational Considerations
- Default Domain Configuration: Knative’s default wildcard domain requires explicit DNS and TLS configuration. Without properly updating
config-domain, services will report URLs but remain externally inaccessible. - Networking Layer Mismatch: Incorrect or missing ingress configurations cause silent routing failures. Always verify Knative’s
config-networksettings align precisely with installed ingress components (Istio, Kourier, etc.). - mTLS and Authorization Policies: Strict mTLS or NetworkPolicies can unintentionally block Knative components (e.g., activator) from scaling workloads. Ensure authorization rules explicitly allow necessary system-level traffic from
knative-serving. - Cold Starts and Scale-to-Zero Tuning: Knative’s scale-to-zero reduces resource consumption but introduces cold-start latency. Adjust readiness probes and the
scale-to-zero-grace-periodconfig parameter (optionallyminScaleif you want to keep a warm replica) to optimize user experience and avoid rapid pod flapping. - Revision Bloat & Garbage Collection: Accumulation of inactive Revisions increases resource overhead and Kubernetes object clutter. Configure Knative’s garbage collection (
config-gc) to retain a sensible number of revisions, regularly auditing unused references. - Resource Overhead and Limits: Knative’s queue-proxy sidecar introduces non-trivial resource overhead at scale. Carefully configure container resource requests/limits and activator autoscaling to ensure cluster stability under traffic bursts.
- Gradual Upgrades & Compatibility: Knative upgrades require sequential, incremental steps to avoid CRD and schema incompatibilities. Carefully review intermediate upgrade notes, verify dependency compatibility, and maintain clear rollback plans.