> For the complete documentation index, see [llms.txt](https://docs.platform9.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.platform9.com/private-cloud-director/2026.4/kubernetes-clusters/cluster-lifecycle/cluster-networking.md).

# Cluster Networking

Kubernetes networking consists of several key components that enable seamless communication between pods, services, and external clients.

## Pod-to-Pod Communication

* Kubernetes assigns each pod a unique IP from the containerCIDR.
* Pods within the same node communicate via the local bridge network.
* Inter-node pod communication is enabled through an overlay network (VXLAN, IP-in-IP) or direct routing.

## Service Networking

* Services expose workloads internally using a virtual IP assigned from the servicesCIDR.
* kube-proxy manages traffic routing using iptables generally.
* External access is provided via LoadBalancer (cloud provider integration), NodePort, or Ingress.

## ContainerCIDR and ServicesCIDR

* Container CIDR defines the range of IPs allocated to pods.
  * The **default** **pod CIDR** for PCD Kubernetes cluster is **10.244.0.0/16**
  * **Must not overlap with PCD Virtualization private networks.**
* Service CIDR defines the range of virtual IPs assigned to services.
  * The **default** **service CIDR** for PCD Kubernetes cluster is **10.96.0.0/16**


---

# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.

## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation by asking a question.

Perform an HTTP GET request on the following URL with the `ask` and `goal` query parameters:

```
GET https://docs.platform9.com/private-cloud-director/2026.4/kubernetes-clusters/cluster-lifecycle/cluster-networking.md?ask=<question>&goal=<user_goal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is what the user is ultimately trying to achieve, the reason they need the answer. Sharing it helps GitBook give you a better, more relevant answer. A goal is most helpful when it describes the outcome the user wants rather than restating the question. For example, with `ask=how do I create an API token`, a goal like `automate deployments from our CI pipeline` lets GitBook tailor the answer to that use case.

The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.