Maintenance Mode
$ ironic node-set-maintenance --reason 'replacing disks' db01.example true
$ ironic node-show db01.example
+------------------------+------------------------------------------------------------
| Property | Value
+------------------------+------------------------------------------------------------
| target_power_state | None
| last_error |
| maintenance_reason | replacing disks
| provision_state | available
| console_enabled | False
| target_provision_state | None
| maintenance | True
| power_state | power off
| instance_uuid | None
| driver_internal_info | {}