$ sc install --etcd-backup-storageclass "standard"
$ kubectl logs etcd-cluster-0000 -n service-catalog
...
2018-05-29 09:40:31.005798 I | embed: listening for peers on http://0.0.0.0:2380
2018-05-29 09:40:31.005827 I | embed: listening for client requests on 0.0.0.0:2379
2018-05-29 09:41:21.014896 W | pkg/netutil: failed resolving host etcd-cluster-0000.etcd-cluster.service-catalog.svc:2380 (lookup etcd-cluster-0000.etcd-cluster.service-catalog.svc on 10.10.0.3:53: read udp 10.10.64.49:59852->10.10.0.3:53: i/o timeout); retrying in 1s
2018-05-29 09:41:21.014944 E | pkg/netutil: could not resolve host etcd-cluster-0000.etcd-cluster.service-catalog.svc:2380
2018-05-29 09:41:21.022469 I | etcdmain: --initial-cluster must include etcd-cluster-0000=http://etcd-cluster-0000.etcd-cluster.service-catalog.svc:2380 given --initial-advertise-peer-urls=http://etcd-cluster-0000.etcd-cluster.service-catalog.svc:2380
2018-05-29 09:41:21.022505 I | etcdmain: forgot to set --initial-cluster flag?
2018-05-29 09:41:21.022513 I | etcdmain: if you want to use discovery service, please set --discovery flag.
Using master branch.
etcd:3.0.17
service-catalog:v0.1.11-gke.0
etcd-operator:v0.6.1
OS: Ubuntu 16.04.4 LTS
Kernel: 4.4.0-124-generic
Docker: 17.3.2
kubeletVersion: v1.9.5