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Chapter 2. Preparing Ceph Storage nodes for deployment

Red Hat Ceph Storage nodes are bare metal systems with IPMI power management. Director installs Red Hat Enterprise Linux on each node.

Director communicates with each node through the Provisioning network during the introspection and provisioning processes. All nodes connect to the Provisioning network through the native VLAN.

For more information about bare metal provisioning before overcloud deployment, see Provisioning and deploying your overcloud in Director Installation and Usage guide.

For a complete guide to bare metal provisioning, see Bare Metal Provisioning.

2.1. Cleaning Ceph Storage node disks
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Ceph Storage OSDs and journal partitions require factory clean disks. All data and metadata must be erased by the Bare Metal Provisioning service (ironic) from these disks before installing the Ceph OSD services.

You can configure director to delete all disk data and metadata by default by using the Bare Metal Provisioning service. When director is configured to perform this task, the Bare Metal Provisioning service performs an additional step to boot the nodes each time a node is set to available.

Warning

The Bare Metal Provisioning service uses the wipefs --force --all command. This command deletes all data and metadata on the disk but it does not perform a secure erase. A secure erase takes much longer.

Procedure

  1. Open /home/stack/undercloud.conf and add the following parameter: 

    clean_nodes=true
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  2. Save /home/stack/undercloud.conf.

  3. Update the undercloud configuration. 

    openstack undercloud install
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2.2. Registering nodes
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Register the nodes to enable communication with director.

Procedure

  1. Create a node inventory JSON file in /home/stack.

  2. Enter hardware and power management details for each node.

    For example: 

    {
    "nodes":[
        {
            "mac":[
                "b1:b1:b1:b1:b1:b1"
            ],
            "cpu":"4",
            "memory":"6144",
            "disk":"40",
            "arch":"x86_64",
            "pm_type":"ipmi",
            "pm_user":"admin",
            "pm_password":"p@55w0rd!",
            "pm_addr":"192.0.2.205"
        },
        {
            "mac":[
                "b2:b2:b2:b2:b2:b2"
            ],
            "cpu":"4",
            "memory":"6144",
            "disk":"40",
            "arch":"x86_64",
            "pm_type":"ipmi",
            "pm_user":"admin",
            "pm_password":"p@55w0rd!",
            "pm_addr":"192.0.2.206"
        },
        {
            "mac":[
                "b3:b3:b3:b3:b3:b3"
            ],
            "cpu":"4",
            "memory":"6144",
            "disk":"40",
            "arch":"x86_64",
            "pm_type":"ipmi",
            "pm_user":"admin",
            "pm_password":"p@55w0rd!",
            "pm_addr":"192.0.2.207"
        },
        {
            "mac":[
                "c1:c1:c1:c1:c1:c1"
            ],
            "cpu":"4",
            "memory":"6144",
            "disk":"40",
            "arch":"x86_64",
            "pm_type":"ipmi",
            "pm_user":"admin",
            "pm_password":"p@55w0rd!",
            "pm_addr":"192.0.2.208"
        },
        {
            "mac":[
                "c2:c2:c2:c2:c2:c2"
            ],
            "cpu":"4",
            "memory":"6144",
            "disk":"40",
            "arch":"x86_64",
            "pm_type":"ipmi",
            "pm_user":"admin",
            "pm_password":"p@55w0rd!",
            "pm_addr":"192.0.2.209"
        },
        {
            "mac":[
                "c3:c3:c3:c3:c3:c3"
            ],
            "cpu":"4",
            "memory":"6144",
            "disk":"40",
            "arch":"x86_64",
            "pm_type":"ipmi",
            "pm_user":"admin",
            "pm_password":"p@55w0rd!",
            "pm_addr":"192.0.2.210"
        },
        {
            "mac":[
                "d1:d1:d1:d1:d1:d1"
            ],
            "cpu":"4",
            "memory":"6144",
            "disk":"40",
            "arch":"x86_64",
            "pm_type":"ipmi",
            "pm_user":"admin",
            "pm_password":"p@55w0rd!",
            "pm_addr":"192.0.2.211"
        },
        {
            "mac":[
                "d2:d2:d2:d2:d2:d2"
            ],
            "cpu":"4",
            "memory":"6144",
            "disk":"40",
            "arch":"x86_64",
            "pm_type":"ipmi",
            "pm_user":"admin",
            "pm_password":"p@55w0rd!",
            "pm_addr":"192.0.2.212"
        },
        {
            "mac":[
                "d3:d3:d3:d3:d3:d3"
            ],
            "cpu":"4",
            "memory":"6144",
            "disk":"40",
            "arch":"x86_64",
            "pm_type":"ipmi",
            "pm_user":"admin",
            "pm_password":"p@55w0rd!",
            "pm_addr":"192.0.2.213"
        }
    ]
}
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  3. Save the new file.

  4. Initialize the stack user: 

    $ source ~/stackrc
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  5. Import the JSON inventory file into director and register nodes 

    $ openstack overcloud node import <inventory_file>
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    Replace <inventory_file> with the name of the file created in the first step.

  6. Assign the kernel and ramdisk images to each node: 

    $ openstack overcloud node configure <node>
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Verify all required packages are available to avoid overcloud deployment failures.

2.3.1. Verifying cephadm package installation
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Verify the cephadm package is installed on at least one overcloud node. The cephadm package is used to bootstrap the first node of the Ceph Storage cluster.

The cephadm package is included in the overcloud-hardened-uefi-full.qcow2 image. The tripleo_cephadm role uses the Ansible package module to ensure it is present in the image.

Ceph Storage nodes typically use multiple disks. Director must identify the root disk in multiple disk configurations. The overcloud image is written to the root disk during the provisioning process.

Hardware properties are used to identify the root disk. For more information about properties you can use to identify the root disk, see Section 2.4.1, “Properties that identify the root disk”.

Procedure

  1. Verify the disk information from the hardware introspection of each node: 

    (undercloud)$ openstack baremetal introspection data save <node_uuid> | --file <output_file_name>
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    • Replace <node_uuid> with the UUID of the node.

    • Replace <output_file_name> with the name of the file that contains the output of the node introspection.

      For example, the data for one node might show three disks: 

      [
  {
    "size": 299439751168,
    "rotational": true,
    "vendor": "DELL",
    "name": "/dev/sda",
    "wwn_vendor_extension": "0x1ea4dcc412a9632b",
    "wwn_with_extension": "0x61866da04f3807001ea4dcc412a9632b",
    "model": "PERC H330 Mini",
    "wwn": "0x61866da04f380700",
    "serial": "61866da04f3807001ea4dcc412a9632b"
  }
  {
    "size": 299439751168,
    "rotational": true,
    "vendor": "DELL",
    "name": "/dev/sdb",
    "wwn_vendor_extension": "0x1ea4e13c12e36ad6",
    "wwn_with_extension": "0x61866da04f380d001ea4e13c12e36ad6",
    "model": "PERC H330 Mini",
    "wwn": "0x61866da04f380d00",
    "serial": "61866da04f380d001ea4e13c12e36ad6"
  }
  {
    "size": 299439751168,
    "rotational": true,
    "vendor": "DELL",
    "name": "/dev/sdc",
    "wwn_vendor_extension": "0x1ea4e31e121cfb45",
    "wwn_with_extension": "0x61866da04f37fc001ea4e31e121cfb45",
    "model": "PERC H330 Mini",
    "wwn": "0x61866da04f37fc00",
    "serial": "61866da04f37fc001ea4e31e121cfb45"
  }
]
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  2. Set the root disk for the node by using a unique hardware property:

    (undercloud)$ openstack baremetal node set --property root_device='{<property_value>}' <node-uuid>

    • Replace <property_value> with the unique hardware property value from the introspection data to use to set the root disk.

    • Replace <node_uuid> with the UUID of the node.

      Note

      A unique hardware property is any property from the hardware introspection step that uniquely identifies the disk. For example, the following command uses the disk serial number to set the root disk:

      (undercloud)$ openstack baremetal node set --property root_device='{"serial": "61866da04f380d001ea4e13c12e36ad6"}' 1a4e30da-b6dc-499d-ba87-0bd8a3819bc0

  3. Configure the BIOS of each node to first boot from the network and then the root disk.

Director identifies the specific disk to use as the root disk. When you run the openstack overcloud node provision command, director provisions and writes the overcloud image to the root disk.

2.4.1. Properties that identify the root disk
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There are several properties that you can define to help director identify the root disk:

  • model (String): Device identifier.
  • vendor (String): Device vendor.
  • serial (String): Disk serial number.
  • hctl (String): Host:Channel:Target:Lun for SCSI.
  • size (Integer): Size of the device in GB.
  • wwn (String): Unique storage identifier.
  • wwn_with_extension (String): Unique storage identifier with the vendor extension appended.
  • wwn_vendor_extension (String): Unique vendor storage identifier.
  • rotational (Boolean): True for a rotational device (HDD), otherwise false (SSD).
  • name (String): The name of the device, for example: /dev/sdb1.
Important

Use the name property for devices with persistent names. Do not use the name property to set the root disk for devices that do not have persistent names because the value can change when the node boots.

The default image for a Red Hat OpenStack Platform (RHOSP) deployment is overcloud-hardened-uefi-full.qcow2. The overcloud-hardened-uefi-full.qcow2 image uses a valid Red Hat OpenStack Platform (RHOSP) subscription. You can use the overcloud-minimal image when you do not want to consume your subscription entitlements, to avoid reaching the limit of your paid Red Hat subscriptions. This is useful, for example, when you want to provision nodes with only Ceph daemons, or when you want to provision a bare operating system (OS) where you do not want to run any other OpenStack services. For information about how to obtain the overcloud-minimal image, see Obtaining images for overcloud nodes.

Note

The overcloud-minimal image supports only standard Linux bridges. The overcloud-minimal image does not support Open vSwitch (OVS) because OVS is an OpenStack service that requires a Red Hat OpenStack Platform subscription entitlement. OVS is not required to deploy Ceph Storage nodes. Use linux_bond instead of ovs_bond to define bonds.

Procedure

  1. Open your /home/stack/templates/overcloud-baremetal-deploy.yaml file.

  2. Add or update the image property for the nodes that you want to use the overcloud-minimal image. You can set the image to overcloud-minimal on specific nodes, or for all nodes for a role.

    Note

    The overcloud minimal image is not a whole disk image. The kernel and ramdisk must be specified in the /home/stack/templates/overcloud-baremetal-deploy.yaml file.

    Specific nodes

    - name: Ceph
  count: 3
  instances:
  - hostname: overcloud-ceph-0
    name: node00
    image:
      href: file:///var/lib/ironic/images/overcloud-minimal.raw
      kernel: file://var/lib/ironic/images/overcloud-minimal.vmlinuz
      ramdisk: file://var/lib/ironic/images/overcloud-minimal.initrd
  - hostname: overcloud-ceph-1
    name: node01
    image:
      href: file:///var/lib/ironic/images/overcloud-minimal.raw
      kernel: file://var/lib/ironic/images/overcloud-minimal.vmlinuz
      ramdisk: file://var/lib/ironic/images/overcloud-minimal.initrd
  - hostname: overcloud-ceph-2
    name: node02
    image:
      href: file:///var/lib/ironic/images/overcloud-minimal.raw
      kernel: file://var/lib/ironic/images/overcloud-minimal.vmlinuz
      ramdisk: file://var/lib/ironic/images/overcloud-minimal.initrd
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    All nodes for a specific role

    - name: Ceph
  count: 3
  defaults:
    image:
      href: file:///var/lib/ironic/images/overcloud-minimal.raw
      kernel: file://var/lib/ironic/images/overcloud-minimal.vmlinuz
      ramdisk: file://var/lib/ironic/images/overcloud-minimal.initrd
  instances:
  - hostname: overcloud-ceph-0
    name: node00
  - hostname: overcloud-ceph-1
    name: node01
  - hostname: overcloud-ceph-2
    name: node02
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  3. In the roles_data.yaml role definition file, set the rhsm_enforce parameter to False. 

    rhsm_enforce: False
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  4. Run the provisioning command: 

    (undercloud)$ openstack overcloud node provision \
--stack overcloud \
--output /home/stack/templates/overcloud-baremetal-deployed.yaml \
/home/stack/templates/overcloud-baremetal-deploy.yaml
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  5. Pass the overcloud-baremetal-deployed.yaml environment file to the openstack overcloud ceph deploy command.

2.6. Designating nodes for Red Hat Ceph Storage
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To designate nodes for Red Hat Ceph Storage, you must create a new role file to configure the CephStorage role, and configure the bare metal nodes with a resource class for CephStorage.

Procedure

  1. Log in to the undercloud as the stack user.

  2. Source the stackrc file: 

    [stack@director ~]$ source ~/stackrc
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  3. Generate a new roles data file named roles_data.yaml that includes the Controller, Compute, and CephStorage roles: 

    (undercloud)$ openstack overcloud roles \
 generate Controller Compute CephStorage -o /home/stack/templates/roles_data.yaml \
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  4. Open roles_data.yaml and ensure it has the following parameters and sections:

    Expand
    Section/ParameterValue

    Role comment

    Role: CephStorage

    Role name

    name: CephStorage

    description

    Ceph node role

    HostnameFormatDefault

    %stackname%-novaceph-%index%

    deprecated_nic_config_name

    ceph.yaml

  5. Register the Ceph nodes for the overcloud by adding them to your node definition template.

  6. Inspect the node hardware: 

    (undercloud)$ openstack overcloud node introspect --all-manageable --provide
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  7. Tag each bare metal node that you want to designate for Ceph with a custom Ceph resource class: 

    (undercloud)$ openstack baremetal node set \
 --resource-class baremetal.CEPH <node>
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    Replace <node> with the ID of the bare metal node.

  8. Add the CephStorage role to your overcloud-baremetal-deploy.yaml file, and define any predictive node placements, resource classes, or other attributes that you want to assign to your nodes: 

    - name: Controller
  	  count: 3
- name: Compute
 	  count: 3
- name: CephStorage
	  count: 5
    defaults:
	    resource_class: baremetal.CEPH
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  9. Run the provisioning command: 

    (undercloud)$ openstack overcloud node provision \
--stack stack \
--output /home/stack/templates/overcloud-baremetal-deployed.yaml \
/home/stack/templates/overcloud-baremetal-deploy.yaml
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  10. Monitor the provisioning progress in a separate terminal. When provisioning is successful, the node state changes from available to active: 

    (undercloud)$ watch openstack baremetal node list
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