Internal and external ingress-nginx controller

[mojtabaimani]

Title: Integrate Internal and External ingress-nginx for Internal and External Services

Description:

To enhance the flexibility and security of Kuberise, we propose integrating both internal and external ingress-nginx controllers. This will allow us to manage internal services separately from external services, providing better control over traffic routing, security policies, and resource allocation.

Objectives:

1. Deploy two instances of ingress-nginx controllers:
   • Internal ingress-nginx: Handles traffic for services that are only accessible within the cluster.
   • External ingress-nginx: Manages traffic for services that need to be exposed outside the cluster.
2. Ensure that both ingress-nginx controllers can coexist without conflicts.
3. Provide configurations and templates for easy setup and customization.
4. Document the setup and usage guidelines for developers and platform engineers.

Tasks:

1. Setup Helm charts:

   • Modify existing Helm charts or create new ones to support dual ingress-nginx deployment.
   • Include configuration options for internal and external ingress-nginx controllers.

2. Configuration:

   • Define separate namespaces and resource quotas for internal and external ingress-nginx controllers.
   • Set up appropriate RBAC rules to restrict access and control over each ingress controller.

3. Ingress Class Definitions:

   • Create distinct ingress classes for internal and external services.
   • Ensure that internal services are only routed through the internal ingress-nginx and vice versa.

4. Annotations and Labels:

   • Implement necessary annotations and labels for services to specify which ingress controller should handle the traffic.

5. Documentation:

   • Write comprehensive documentation detailing:
     • The purpose and benefits of using dual ingress-nginx controllers.
     • Step-by-step instructions for setting up and configuring both internal and external ingress-nginx.
     • Best practices for maintaining and troubleshooting the ingress controllers.

6. Testing:

   • Perform thorough testing to ensure that both ingress controllers function as expected.
   • Validate that internal services are not accessible from outside the cluster.
   • Confirm that external services are correctly exposed and accessible.

Benefits:

• Improved security by isolating internal traffic from external exposure.
• Enhanced control over resource allocation for ingress traffic.
• Simplified management of services with clear segregation of internal and external endpoints.
• Greater flexibility in applying security policies and traffic routing rules.

[mojtabaimani]

Motivation

Using an internal ingress-nginx alongside an external ingress-nginx in a Kubernetes environment offers several benefits, even though services can be accessed directly via their service addresses and load balancing is already managed by Kubernetes. Here are some of the key benefits of using an internal ingress-nginx:

1. Security and Access Control

• Internal Segmentation: Internal ingress-nginx allows you to segment traffic within your cluster, ensuring that internal services are not exposed externally. This minimizes the attack surface and enhances security by restricting access to sensitive services to only internal traffic.
• Policy Enforcement: You can enforce internal policies such as IP whitelisting, rate limiting, and authentication on internal traffic, ensuring that only authorized internal clients can access certain services.

2. Consistent Access Management

• Uniform Entry Point: Internal ingress provides a consistent access point for internal services. This uniformity simplifies the configuration and management of internal service access, as all internal traffic goes through a single ingress point.
• Simplified DNS Management: By using internal ingress, internal services can be accessed via DNS names, similar to how external services are accessed. This consistency simplifies the service discovery process for developers and applications within the cluster.

3. Enhanced Load Balancing

• Advanced Load Balancing Features: While Kubernetes services provide basic load balancing, ingress controllers often support more advanced load balancing algorithms and features such as session persistence, custom load balancing rules, and weighted traffic distribution.

4. Monitoring and Logging

• Centralized Monitoring: Internal ingress-nginx can be configured to log and monitor internal traffic, providing insights into traffic patterns, performance issues, and potential security incidents. This centralized monitoring is more manageable than having distributed logs from multiple services.
• Metrics Collection: You can collect metrics from the internal ingress to monitor the health and performance of your internal services, which can be integrated with monitoring tools like Prometheus and Grafana.

5. Traffic Management

• Traffic Shaping and Rate Limiting: Internal ingress controllers can manage traffic more efficiently by implementing traffic shaping, rate limiting, and traffic throttling for internal services. This helps in preventing any single service from overwhelming the network or other services.
• A/B Testing and Canary Releases: Internal ingress can facilitate A/B testing and canary releases within the internal network by directing a subset of traffic to different versions of a service, helping in safer and more controlled deployments.

6. Simplified Configuration Management

• Ingress Resources: Using ingress resources, you can define routing rules, SSL termination, and other configurations in a declarative manner. This makes it easier to manage and update configurations compared to directly configuring each service.
• Consistent Configurations: Ensuring consistent ingress configurations across internal and external services can reduce configuration drift and simplify overall management.

7. Isolation of Environments

• Development and Testing: Internal ingress-nginx can be used to create isolated environments for development, testing, or staging within the same cluster, allowing different teams to work independently without affecting external traffic.

In summary, using an internal ingress-nginx provides enhanced security, consistent access management, advanced traffic control, and centralized monitoring and logging, all of which contribute to a more robust and manageable Kubernetes environment.