<p>I checked the pods in the kube-system namespace and noticed that some pods share the same ip address.The pods that share the same ip address appear to be on the same node.</p>

<p><a href="https://i.stack.imgur.com/OSiy0.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/OSiy0.png" alt="enter image description here"></a> </p>

<p>In the Kubernetes documenatation it said that "Evert pod gets its own ip address." (<a href="https://kubernetes.io/docs/concepts/cluster-administration/networking/" rel="nofollow noreferrer">https://kubernetes.io/docs/concepts/cluster-administration/networking/</a>). I'm confused as to how same ip for some pods came about.</p>

<p>This was reported in <a href="https://github.com/kubernetes/kubernetes/issues/51322" rel="noreferrer">issue 51322</a> and can depend on the <a href="https://kubernetes.io/docs/concepts/extend-kubernetes/compute-storage-net/network-plugins/" rel="noreferrer">network plugin</a> you are using.</p>

<p>The issue was seen when using the basic <a href="https://kubernetes.io/docs/concepts/extend-kubernetes/compute-storage-net/network-plugins/#kubenet" rel="noreferrer">kubenet</a> network plugin on Linux.</p>

<p>Sometime, a <a href="https://github.com/kubernetes/kubernetes/issues/51322#issuecomment-388517154" rel="noreferrer">reset/reboot can help</a></p>

<blockquote>
  <p>I suspect nodes have been configured with overlapped podCIDRs for such cases.<br>
  The pod CIDR could be checked by <code>kubectl get node -o jsonpath='{.items[*].spec.podCIDR}'</code></p>
</blockquote>
