Changing the Hostname of a Leader Appliance:
1. SSH to the CLI of the Leader Appliance
2. Stop services on the Leader appliance: “services sp stop”
3. Rename the appliance: “service sp device rename old_name new_name”
4. Set the new name on the device: “system name set new_name”
5. Start SP services: “service sp start”
6. Save the configuration: “config write”