Enabling and configuring gateway host

Gateway hosts forward metrics off-cluster. Skip this step if gateway hosts are already configured.

You must add gateway hosts if gateway hosts are not configured. For more information, see the Gateway OpenTelemetry Collector documentation.

Check the current gateway hosts:
```
./obs-cli.sh get-gateway-hosts
```
note
If you are on Cloudera Base on premises airgapped environment or you do not have Cloudera Observability SaaS on your environment, you will get an empty output.
You must add gateway hosts if gateway hosts are not configured. For more information, see the Gateway OpenTelemetry Collector documentation.
```
./obs-cli.sh list-hosts
./obs-cli.sh add-gateway-host --host [***HOST_NAME***]
```
important
The gateway host must have network access to your third-party platform. If that environment is reachable only over your intranet, choose a gateway host that can reach it. For more information on preparing gateway nodes, see Configuring the gateway nodes using Cloudera Manager.