Fairwinds Polaris vs Tetragon

Fairwinds Polaris is an open source policy engine for validating and remediating Kubernetes resource configuration. It includes more than 30 built-in policies, and teams can add their own using JSON Schema. Checks cover security practices such as least privilege, privilege escalation, root execution, and host IPC or PID settings, along with resource requests and limits, readiness and liveness probes, and image tags. Polaris can run as a dashboard, an admission controller, or a command-line tool for checking local YAML files in CI/CD. Its validating webhook rejects workloads that trigger danger-level checks; warning-level findings pass and appear in the dashboard or webhook logs. A mutating webhook or command-line run can automatically remediate supported issues, including missing limits and probes and some unsafe security settings. The dashboard can audit local files or connect to a live cluster, and can be installed with kubectl or Helm. The validating webhook requires a valid TLS certificate. Polaris is free and runs on Linux, macOS, Windows, web, and self-hosted environments.

Tetragon is a Kubernetes-aware security observability and runtime enforcement tool for Linux, container, and Kubernetes workloads. It uses eBPF to monitor activity, filter events, and enforce policies in the kernel in real time. Process reports can include executed binaries, command-line arguments, user IDs, parent processes, and start times. Tetragon also monitors file access and changes, and can block unauthorized file operations at the kernel level. Kubernetes policies can filter activity by namespace, pod labels, and container fields, with support for containerd and CRI-O. Network visibility ties events to processes and workloads and tracks connections, socket lifecycle, and bytes sent or received. The tool also monitors credential changes, kernel module activity, and eBPF program loads and interactions. Findings are available as JSON logs or through gRPC. Installation options include Helm on Kubernetes, released Linux packages, and a container image. Tetragon is a Cilium sub-project and a CNCF project, and is available as an open-source project with no paid plans listed.