Kubernetes Ingress: How to Deny Certain Paths in Your Network

Kubernetes Ingress: How to Deny Certain Paths in Your Network

Kubernetes, the open-source platform for automating deployment, scaling, and management of containerized applications, has become a staple in the world of data science. One of its key features is the Ingress, a powerful tool for managing external access to services within a cluster. This blog post will guide you through the process of denying certain paths in your Kubernetes Ingress network, a crucial skill for maintaining security and control over your applications.

What is Kubernetes Ingress?

Before we dive into the specifics, let’s briefly discuss what Kubernetes Ingress is. Ingress is an API object that manages external access to the services in a cluster, typically HTTP and HTTPS. It can provide load balancing, SSL termination, and name-based virtual hosting, among other features.

Ingress is not a service type, but it acts as the entry point for your cluster. It allows you to define:

• How traffic should be routed based on host or path.
• How services should be exposed outside your cluster.
• How to apply SSL certificates.
• How to restrict paths or hosts.

Denying Paths in Kubernetes Ingress

Now, let’s focus on how to deny certain paths in your Kubernetes Ingress network. This is particularly useful when you want to restrict access to certain parts of your application for security reasons.

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: ingress-with-deny-paths
spec:
  rules:
  - host: myapp.mydomain.com
    http:
      paths:
      - pathType: Prefix
        path: "/deny"
        backend:
          service:
            name: my-service
            port:
              number: 80

In the above YAML configuration, we’ve defined an Ingress rule for the host myapp.mydomain.com. The pathType: Prefix and path: "/deny" mean that any path that starts with /deny will be routed to the my-service service on port 80.

However, this doesn’t deny the path yet. To do this, we need to use an annotation. Annotations allow you to attach arbitrary non-identifying metadata to objects. In this case, we’ll use the nginx.ingress.kubernetes.io/whitelist-source-range annotation to restrict access to certain IP addresses.

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: ingress-with-deny-paths
  annotations:
    nginx.ingress.kubernetes.io/whitelist-source-range: "0.0.0.0/0,!192.168.0.0/16"
spec:
  rules:
  - host: myapp.mydomain.com
    http:
      paths:
      - pathType: Prefix
        path: "/deny"
        backend:
          service:
            name: my-service
            port:
              number: 80

In this configuration, we’ve added the nginx.ingress.kubernetes.io/whitelist-source-range annotation with the value "0.0.0.0/0,!192.168.0.0/16". This means that all IP addresses (0.0.0.0/0) are allowed to access the /deny path, except for those in the 192.168.0.0/16 range.

Conclusion

Denying certain paths in your Kubernetes Ingress network is a powerful way to maintain control and security over your applications. By understanding how to use Ingress rules and annotations, you can effectively manage external access to the services within your cluster.

Remember, Kubernetes is a complex system, and its features often interact in intricate ways. Always test your configurations in a safe environment before deploying them to production.

Stay tuned for more posts on Kubernetes and other data science topics. If you have any questions or comments, feel free to reach out. Happy coding!

Keywords: Kubernetes, Ingress, Deny Paths, Network, Data Science, Security, Cluster, Configuration, Annotations, IP Addresses, YAML, Load Balancing, SSL Termination, Virtual Hosting, API Object, Services, Metadata, nginx.ingress.kubernetes.io/whitelist-source-range

Meta Description: Learn how to deny certain paths in your Kubernetes Ingress network for better control and security over your applications. This guide provides a step-by-step approach to using Ingress rules and annotations.

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