<p>I have a K8s cluster created with kubeadm that consists of a master node and two workers.</p>

<p>I am following this documentation article regarding the etcd backup: <a href="https://kubernetes.io/docs/tasks/administer-cluster/configure-upgrade-etcd/#backing-up-an-etcd-cluster" rel="noreferrer">https://kubernetes.io/docs/tasks/administer-cluster/configure-upgrade-etcd/#backing-up-an-etcd-cluster</a></p>

<p>I have to use etcdctl to backup the etcd db so I sh into the etcd pod running on the master node to do it from there: <code>kubectl exec -it -n kube-system etcd-ip-x-x-x-x sh</code></p>

<p>NOTE: The master node hosts the etcd database in this path <code>/var/lib/etcd</code> which is mounted on the pod as a VolumeMount in <code>/var/lib/etcd</code>.</p>

<p>Following the doc I run: <code>ETCDCTL_API=3 etcdctl --endpoints 127.0.0.1:2379 snapshot save snapshotdb</code> and it returns the following error:</p>

<pre><code>Error:  rpc error: code = 13 desc = transport: write tcp 127.0.0.1:44464-&gt;127.0.0.1:2379: write: connection reset by peer
</code></pre>

<p>What is the problem here?</p>

<p>I managed to make it work adding the certificates info to the command:</p>

<pre><code>ETCDCTL_API=3 etcdctl --endpoints https://127.0.0.1:2379 --cacert=/etc/kubernetes/pki/etcd/ca.crt --cert=/etc/kubernetes/pki/etcd/healthcheck-client.crt --key /etc/kubernetes/pki/etcd/healthcheck-client.key snapshot save ./snapshot.db
</code></pre>
