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Chapter 17. Automatically Discover Bare Metal Nodes

You can use auto-discovery to register overcloud nodes and generate their metadata, without first having to create an instackenv.json file. This improvement can help reduce the time spent initially collecting information about a node, for example, removing the need to collate the IPMI IP addresses and subsequently create the instackenv.json.

17.1. Requirements
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  • All overcloud nodes BMCs must be configured to be accessible to director through the IPMI.
  • All overcloud nodes must be configured to PXE boot from the NIC connected to the undercloud control plane network.

17.2. Enable Auto-discovery
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  1. Enable Bare Metal auto-discovery in undercloud.conf: 

    enable_node_discovery = True
discovery_default_driver = ipmi
    • enable_node_discovery - When enabled, any node that boots the introspection ramdisk using PXE will be enrolled in ironic.
    • discovery_default_driver - Sets the driver to use for discovered nodes. For example, ipmi.

  2. Add your IPMI credentials to ironic:

    1. Add your IPMI credentials to a file named ipmi-credentials.json. You must replace the SampleUsername, RedactedSecurePassword, and bmc_address values in this example to suit your environment: 

      [
    {
        "description": "Set default IPMI credentials",
        "conditions": [
            {"op": "eq", "field": "data://auto_discovered", "value": true}
        ],
        "actions": [
            {"action": "set-attribute", "path": "driver_info/ipmi_username",
             "value": "SampleUsername"},
            {"action": "set-attribute", "path": "driver_info/ipmi_password",
             "value": "RedactedSecurePassword"},
            {"action": "set-attribute", "path": "driver_info/ipmi_address",
             "value": "{data[inventory][bmc_address]}"}
        ]
    }
]

  3. Import the IPMI credentials file into ironic: 

    $ openstack baremetal introspection rule import ipmi-credentials.json

17.3. Test Auto-discovery
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  1. Power on the required nodes.

  2. Run the openstack baremetal node list command. You should see the new nodes listed in an enrolled state: 

    $ openstack baremetal node list
+--------------------------------------+------+---------------+-------------+--------------------+-------------+
| UUID                                 | Name | Instance UUID | Power State | Provisioning State | Maintenance |
+--------------------------------------+------+---------------+-------------+--------------------+-------------+
| c6e63aec-e5ba-4d63-8d37-bd57628258e8 | None | None          | power off   | enroll             | False       |
| 0362b7b2-5b9c-4113-92e1-0b34a2535d9b | None | None          | power off   | enroll             | False       |
+--------------------------------------+------+---------------+-------------+--------------------+-------------+

  3. Set the resource class for each node: 

    $ for NODE in `openstack baremetal node list -c UUID -f value` ; do openstack baremetal node set $NODE --resource-class baremetal ; done

  4. Configure the kernel and ramdisk for each node: 

    $ for NODE in `openstack baremetal node list -c UUID -f value` ; do openstack baremetal node manage $NODE ; done
$ openstack overcloud node configure --all-manageable

  5. Set all nodes to available: 

    $ for NODE in `openstack baremetal node list -c UUID -f value` ; do openstack baremetal node provide $NODE ; done

If you have a heterogeneous hardware environment, you can use introspection rules to assign credentials and remote management credentials. For example, you might want a separate discovery rule to handle your Dell nodes that use DRAC:

  1. Create a file named dell-drac-rules.json with the following contents: 

    [
    {
        "description": "Set default IPMI credentials",
        "conditions": [
            {"op": "eq", "field": "data://auto_discovered", "value": true},
            {"op": "ne", "field": "data://inventory.system_vendor.manufacturer",
             "value": "Dell Inc."}
        ],
        "actions": [
            {"action": "set-attribute", "path": "driver_info/ipmi_username",
             "value": "SampleUsername"},
            {"action": "set-attribute", "path": "driver_info/ipmi_password",
             "value": "RedactedSecurePassword"},
            {"action": "set-attribute", "path": "driver_info/ipmi_address",
             "value": "{data[inventory][bmc_address]}"}
        ]
    },
    {
        "description": "Set the vendor driver for Dell hardware",
        "conditions": [
            {"op": "eq", "field": "data://auto_discovered", "value": true},
            {"op": "eq", "field": "data://inventory.system_vendor.manufacturer",
             "value": "Dell Inc."}
        ],
        "actions": [
            {"action": "set-attribute", "path": "driver", "value": "idrac"},
            {"action": "set-attribute", "path": "driver_info/drac_username",
             "value": "SampleUsername"},
            {"action": "set-attribute", "path": "driver_info/drac_password",
             "value": "RedactedSecurePassword"},
            {"action": "set-attribute", "path": "driver_info/drac_address",
             "value": "{data[inventory][bmc_address]}"}
        ]
    }
]

    You must replace the username and password values in this example to suit your environment:

  2. Import the rule into ironic: 

    $ openstack baremetal introspection rule import dell-drac-rules.json
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