<p>I have a K8S cluster versioned 1.11.</p>

<p>I have calico installed as cni plugin.
I need to replace it with flannel.</p>

<p>I found guides online how to migrate from flannel to calico but not the other way around.</p>

<p>Down any one have a tip/idea how to get by this?</p>

<p>Is it even possible migrating from Calico to flannel?</p>

<p>Thanks</p>

<p>Migrating a cluster from Flannel to Calico is feasible but migration from Calico to Flannel is not supported.</p>

<p>This is mentioned in the documentation provided by <a href="https://docs.projectcalico.org/v3.9/getting-started/kubernetes/installation/migration-from-flannel" rel="nofollow noreferrer">Calico</a>:</p>

<blockquote>
  <p><strong>Rollback</strong>: Migration from Calico to flannel is not supported.</p>
</blockquote>
