In the etcd container, the etcd data directory is always /var/lib/etcd. Reverting to this value, since etcd_data_dir on the host maps to /var/lib/etcd in the container.

roles/etcd/templates/etcd.env.yml

@@ -1,4 +1,4 @@
-ETCD_DATA_DIR={{ etcd_data_dir }}
+ETCD_DATA_DIR=/var/lib/etcd
 ETCD_ADVERTISE_CLIENT_URLS={{ etcd_client_url }}
 ETCD_INITIAL_ADVERTISE_PEER_URLS={{ etcd_peer_url }}
 ETCD_INITIAL_CLUSTER_STATE={% if etcd_cluster_is_healthy.rc != 0 | bool %}new{% else %}existing{% endif %}