How do namespaces isolate resources?

Namespaces isolate resources in Kubernetes by creating logical partitions within a cluster. Here’s how they achieve this isolation:

1. Resource Grouping: Each namespace can contain its own set of resources, such as pods, services, and deployments. This means that resources in one namespace do not interfere with those in another, allowing for better organization and management.

2. Name Collision Prevention: Resources within different namespaces can have the same name. For example, you can have a pod named web in both the dev and prod namespaces without conflict. This prevents name collisions and allows for clearer resource management.

3. Access Control: Namespaces enable the implementation of Role-Based Access Control (RBAC). You can define roles and permissions that apply only to specific namespaces, restricting users or service accounts from accessing resources in other namespaces.

4. Resource Quotas: You can set resource quotas on a per-namespace basis, limiting the amount of CPU and memory that can be consumed by resources within that namespace. This ensures that one namespace cannot exhaust cluster resources, thereby isolating resource usage.

5. Network Policies: Namespaces allow you to define network policies that control traffic between pods. This means you can restrict communication between pods in different namespaces, enhancing security and isolation.

By using namespaces, Kubernetes provides a way to logically separate and manage resources, ensuring that workloads are isolated from one another while still operating within the same cluster.