# Troubleshooting Calico Add-on

## Problem

Calico handles network connectivity for PCD-K clusters. As a critical core add-on for PCD-K clusters, a broken Calico functionality significantly impacts networking. When Calico experiences issues, here's a general guide on how to troubleshoot Calico Add-on Issues.

## Environment

* Private Cloud Director - v2025.4 and Higher.
* Kubernetes Cluster 1.31.2 or Higher.

## Procedure

1. Validate if the namespaces `calico-apiserver` & `calico-system` are created or not.
2. Confirm all pods are healthy in both namespaces.

**Note:**

The `calico-node-xxxxx` pod should be running on all worker nodes.

3. Review why these pods are in "`CrashLoopBackOff/OOMkilled/Pending/Error`" state, see events sections from the below command output.

```bash
$ kubectl describe <Pod-name> -n <calico-namespace>
```

4. Get more information on the failure from pod logs using command:

{% tabs %}
{% tab title="Command" %}

```bash
$ kubectl logs <Pod-name> -n <calico-namespace>
```

{% endtab %}
{% endtabs %}

5. Verify connectivity to the API server, run:

```bash
$ curl -vk https://<kubernetes-pod-IP>:443/healthz
```

6. If these steps prove insufficient to resolve the issue, kindly reach out to the [Platform9 Support Team](https://support.platform9.com) for additional assistance.

## Most common causes

* The `calico-node` pod is a DaemonSet that runs on every Kubernetes node. If it's not healthy, Calico won't work.
* Connectivity to the API server is broken.


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