Fairwinds Polaris

Overview

Fairwinds Polaris is an open-source policy engine for checking Kubernetes resource configuration and correcting some problems automatically. It suits teams that want policy checks in manifests, CI/CD or a cluster without adding a software license cost. Its choice of run modes is a strength; teams relying on admission enforcement must also manage a valid TLS certificate.

Key features

Polaris ships with more than 30 configuration policies and lets teams define their own with JSON Schema. Checks cover security settings such as privilege escalation, root execution, read-only root filesystems and host IPC or PID use, alongside reliability checks for readiness and liveness probes and efficiency checks for CPU and memory requests and limits. It also flags missing or latest image tags and checks image pull policy. This breadth makes it useful for teams seeking a single pass over security-sensitive defaults and everyday deployment hygiene.

There are three ways to put those checks to work: a dashboard, an admission controller and a command-line tool. The dashboard can run in a cluster through kubectl or Helm, run locally with credentials in KUBECONFIG, or audit local files instead of a live cluster. The CLI can inspect local YAML files in CI/CD, catching issues before workloads are deployed. Teams can therefore adopt Polaris at the point in their workflow that best fits their deployment process.

Admission control distinguishes severity: danger-level findings cause the validating webhook to reject a workload, while warning-level findings pass and appear in the dashboard or webhook logs. That lets teams block selected high-risk configurations without treating every warning as a release blocker. The webhook requires a valid TLS certificate, however, which adds a condition to deploying this mode.

Polaris can automatically remediate supported issues when run through the CLI or mutating webhook. Examples include missing resource limits and probes and some unsafe security settings. That can reduce manual correction, but remediation is limited to supported issues rather than a blanket fix for every policy failure. Polaris container images are signed and their tags immutable; the documentation recommends full version tags or pinning by digest.

Fairwinds Insights can collect Polaris findings across clusters and retain results with remediation guidance. Fairwinds points to Insights for teams that also want multi-cluster history and integrations with Slack, Datadog and Jira, making it a separate consideration for organizations that need more than Polaris's policy checks.

Pricing

Polaris (Open Source): free. The free plan is an open-source policy engine aimed at small teams. It is the natural fit for teams comfortable running and operating the tool themselves; there is no paid Polaris tier described here, so teams wanting Fairwinds Insights capabilities should assess that product separately.

Platforms

Polaris is listed for Linux, macOS, Windows, web and self-hosted use. Its Kubernetes installation options include Helm, and its dashboard can also be run locally with cluster credentials. These options suit teams that want to choose between cluster deployment and local auditing, while the CLI supports local YAML checks in CI/CD.

Who it's for

Polaris is best for Kubernetes teams that want configurable checks on workload security, reliability, resource settings and image practices, particularly when they want to enforce policies at admission or catch problems in CI/CD. It is less suited to teams whose priority is multi-cluster history and integrations such as Slack, Datadog and Jira without adopting Fairwinds Insights as well.

Pros and cons

Broad coverage in an open-source tool: More than 30 built-in policies span security, reliability, resource efficiency and image configuration, with JSON Schema available for custom rules.

Flexible placement in the workflow: Dashboard, admission controller and CLI modes support cluster checks, local audits and pre-deployment CI/CD checks.

Selective blocking and remediation: Danger-level checks can reject workloads, and supported issues such as missing probes or limits can be remediated automatically.

Admission setup has a prerequisite: The validating webhook needs a valid TLS certificate, so teams choosing that mode must account for certificate management.

Cross-cluster history calls for another product: Fairwinds directs teams seeking retained findings and external integrations to Fairwinds Insights.

Alternatives

Kubescape is another free, self-hosted option, with a CLI and Kubernetes operator under the Apache 2.0 license; choose it if that combination better matches how you want to run security checks.

CloudSploit offers a free self-hosted open-source version and a hosted commercial version at Aqua Wave with custom pricing; consider it when you want that hosted option.

Kyverno is a free, Apache-licensed open-source project for teams comparing Kubernetes policy tools.

Monokle is a free, open-source MIT-licensed desktop option from Kubeshop for readers considering a desktop tool.

Red Hat Trusted Artifact Signer is a paid alternative with custom pricing for teams evaluating a commercial option.

KubeArmor is a free open-source runtime security project; workload and platform support varies by its support matrix, so consider it when runtime security is the focus.

bifrost security is a paid option with a free trial for teams that want to evaluate a commercial product.

KSPM Pro is a freemium web product with a free plan for one Kubernetes cluster and real-time scans, suited to readers whose needs fit that stated cap.

Browse Kubernetes Security Software, Infrastructure Policy as Code Tools or Infrastructure as Code Security Software for related categories.

Verdict

Choose Polaris if your Kubernetes team wants a free, open-source way to apply configuration policies across CI/CD, cluster dashboards or admission control, with automatic correction for supported issues. Its breadth and deployment flexibility are compelling; look elsewhere or add Fairwinds Insights if multi-cluster history and integrations are central, and account for TLS certificate management if you need the validating webhook.