readme: add Overview and Getting Started sections
## Overview
-etcd backup operator backups data of an etcd cluster that's deployed on kubernetes.
-
-## Requirements
-* Kubernetes 1.7+
-* etcd 3.1+
+etcd backup operator backups the data of a etcd cluster running on [Kubernetes][Kube] to a remote storage such as AWS [S3][s3].
## Getting Started
-## Documentation
+Try out etcd backup operator by running it on Kubernetes and then create a `EtcdBackup` Custom Resource which contains the targeting etcd cluster and S3 backup config; the etcd backup operator automatically picks up the `EtcdBackup` Custom Resource, retrieves etcd snapshot, and then saves it to S3.
+>Note: The demo uses the `default` namespace.
+
+Prerequisites:
+* access to a Kubernetes environment.
+* see [Instruction][etcd_cluster_deploy] to deploy an etcd cluster.
+
+### Deploy etcd restore operator
+
+Once `example-etcd-cluster` is running, let's create a backup for `example-etcd-cluster` using etcd backup operator.
+
+First, deploy an etcd backup operator:
+> Note: etcd backup operator also creates EtcdBackup CRD when starting.
+
+```sh
+$ kubectl create -f example/etcd-backup-operator/deployment.yaml
+$ kubectl get pod
+NAME READY STATUS RESTARTS AGE
+etcd-backup-operator-1102130733-hhgt7 1/1 Running 0 3s
+```
+
+### Create AWS Secret
+
+Then, create an Kubernetes secret that contains aws config/credential; etcd operator uses the secret to gain access to S3 in order to save the etcd snapshot.
+
+Verify that the local aws config and credentials files exist:
+```sh
+$ cat $AWS_DIR/credentials
+[default]
+aws_access_key_id = XXX
+aws_secret_access_key = XXX
+
+$ cat $AWS_DIR/config
+[default]
+region = <region>
+```
+
+Create kubernetes secret `aws`:
+
+`kubectl create secret generic aws --from-file=$AWS_DIR/credentials --from-file=$AWS_DIR/config`
+
+### Create Backup CR
+
+Fill the template `example/etcd-backup-operator/backup_cr.yaml` with concrete `s3Bucket` and `awsSecret` values and trigger a backup:
+
+```sh
+sed -e 's/<s3-bucket-name>/mybucket/g' \
+ -e 's/<aws-secret>/aws/g' \
+ example/etcd-backup-operator/backup_cr.yaml \
+ | kubectl create -f -
+```
+
+### Verify status
+
+Verify the backup status by checking the `status` section of the `EtcdBackup` CR:
+```
+$ kubectl get EtcdBackup example-etcd-cluster -o yaml
+apiVersion: etcd.database.coreos.com/v1beta2
+kind: EtcdBackup
+...
+status:
+ s3Path: mybucket/v1/default/example-etcd-cluster/3.1.8_0000000000000001_etcd.backup
+ succeeded: true
+```
+
+* `s3Path` is the full S3 object path to the stored etcd backup.
+
+This demonstrates etcd backup operator's basic one time backup functionality.
+
+
+[Kube]:https://github.com/kubernetes/kubernetes
+[s3]:https://aws.amazon.com/s3/
+[etcd_cluster_deploy]:https://github.com/coreos/etcd-operator#create-and-destroy-an-etcd-cluster
+[minikube]:https://github.com/kubernetes/minikube
