use etcdctl to manage (list, delete ...) openshift and kubernetes object. ETCD version 3:
Make sure that you do the backup before any modifications (you better be safe first).
Check openshift official docs
easy_install shyaml
etcd_endpoint="$(cat /etc/origin/master/master-config.yaml | shyaml get-value etcdClientInfo.urls.0)"
cert_file='/etc/origin/master/master.etcd-client.crt'
key_file='/etc/origin/master/master.etcd-client.key'
ca_file="/etc/origin/master/$(cat /etc/origin/master/master-config.yaml | shyaml get-value etcdClientInfo.ca)"
ETCDCTL_API=3 etcdctl --endpoints=${etcd_endpoint} --cert ${cert_file} --key ${key_file} --cacert ${ca_file} get /openshift.io --prefix --keys-only
ETCDCTL_API=3 etcdctl --endpoints=${etcd_endpoint} --cert ${cert_file} --key ${key_file} --cacert ${ca_file} get /kubernetes.io/namespaces --prefix --keys-only
ETCDCTL_API=3 etcdctl --endpoints=${etcd_endpoint} --cert ${cert_file} --key ${key_file} --cacert ${ca_file} del /kubernetes.io/namespaces/test01
ETCDCTL_API=3 etcdctl --endpoints=${etcd_endpoint} --cert ${cert_file} --key ${key_file} --cacert ${ca_file} etcd -h