The issue with the command below is that --data-dir does not point to the correct etcd directory. Visit the etcd.yaml manifest file in /etcd/kubernetes/manifests. Usually, the etcd directory is /var/lib/etcd. Then, provide the backup dir with --backup-dir --/opt/etcd-backup.db
etcdctl --cert-file=/etc/kubernetes/pki/etcd/server.crt --key-file=/etc/kubernetes/pki/etcd/server.key --ca-file=/etc/kubernetes/pki/etcd/ca.crt --endpoints="https://127.0.0.1:2379" backup --data-dir /opt/etcd-backup.db
2025-10-20 13:09:57.332325 I | open /opt/etcd-backup.db/member/snap: no such file or directory