Backing up etcd data

Procedure

Back up the cluster etcd data.
Store the backup in a secure location outside the OpenShift Container Platform environment.
Back up etcd data by creating a snapshot. You must only save a snapshot from a single master host. You do not need a snapshot from each master host in the cluster.
NOTE:
If your cluster is behind a proxy, export proxy on master nodes (applicable only for online mode of installation).
1. Access the master host as a core user.
2. If the cluster-wide proxy is enabled, ensure that you have exported the NO_PROXY, HTTP_PROXY, and HTTPS_PROXY environment variables.
  To check whether the proxy is enabled, run the following command in bastion node:
```
oc get proxy cluster -o yaml
```
  NOTE:
  This step is only applicable in case of online mode of installation.
3. Run the etcd-snapshot-backup.sh script and pass in the location to save the backup to.
```
sudo /usr/local/bin/etcd-snapshot-backup.sh ./assets/backup
```
```
Creating asset directory ./assets
18bcb6966b171d31c574387f5adfcfb0109f56f3cd2c4742db3e1b7d5f4eff
etcdctl version 3.3.17
API version: 3.3
Trying to backup etcd client certs..
etcd client certs found in /etc/kubernetes/static-pod-resources/kube-apiserver-pod-12 backing up to ./assets/backup/
Backing up /etc/kubernetes/manifests/etcd-member.yaml to ./assets/backup/
Trying to backup latest static pod resources..
{"level":"warn","ts":"2020-06-25T08:19:51.500Z","caller":"clientv3/retry_interceptor.go:116","msg":"retry stream intercept"}
Snapshot saved at ./assets/backup/snapshot_2020-06-25_081950.db
snapshot db and kube resources are successfully saved to ./assets/backup!
```
4. Copy the snapshot_<YYYY-MM-DD_HHMMSS>.db file to a secure location outside the cluster.