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Securing the Cloud
The Evolution and Impact of Pod Security Policies
Navigating Through Kubernetes Security Layers: From PSPs to OPA
Pod Security Policies (PSPs) Overview
Pod Security Policies (PSPs), despite being phased out, continue to be widely used. PSPs allow for the automatic application of security settings through the definition of policies that adhere to the PSP API schema. These policies serve as cluster-level regulations, dictating various aspects of pod operation such as permissible actions, access rights, execution identities, etc.
For example, to prohibit all containers in a cluster from operating under the root user, a PSP can be established. Additionally, these policies can restrict containers from obtaining privileged status or from utilizing the host’s network and PID namespaces.
Although PSPs have demonstrated utility, alternatives like the Open Policy Agent (OPA) are becoming more prevalent. OPA, commonly referred to as “oh-pa,” offers a comprehensive policy framework and toolset for centralized configuration across cloud environments. As an admission controller within Kubernetes, OPA can enforce or modify incoming requests. It can be implemented using Custom Resource Definitions with the help of OPA…
