Internet connectivity and pod to pod communication is not working

[varun-thantry]

Description:
I am setting up Kubernetes 1.29 on CentOS 9 using kubeadm and Calico v3.26.1 as the CNI. I followed the installation steps from this article:
🔗 Install Kubernetes on RHEL 9

I applied the following Calico manifests:

tigera-operator.yaml
custom-resources.yaml

Problem:
🚨 Issues observed:

1. Pods cannot access the internet (e.g., curl google.com fails).
2. Pod-to-pod communication is broken (pods on the same and different nodes cannot reach each other).

What I Have Tried:

1. Verified Calico pods are running:

kubectl get pods -n calico-system

2. Checked if IP forwarding is enabled:

sysctl net.ipv4.ip_forward
✅ It is set to 1.

3. Examined calico-node logs:
   kubectl logs -n calico-system -l k8s-app=calico-node

Environment Details:
Kubernetes Version: 1.29
Calico Version: v3.26.1
OS: CentOS Stream 9
Installation Method: kubeadm

Expected Behavior:

1. Pods should be able to access external networks.
2. Pod-to-pod communication should work seamlessly.

Actual Behavior:

1. No internet access from inside the pod.
2. Pods cannot reach each other (both within and across nodes).

Questions:

1. Does Calico v3.26.1 fully support Kubernetes 1.29 on CentOS 9?
2. Are there additional configurations required for networking on CentOS 9?
3. How can I further debug and fix this issue?