Create flavors for use with the Bare Metal service

You’ll need to create a special bare metal flavor in the Compute service. The flavor is mapped to the bare metal node through the node’s resource_class field (available starting with Bare Metal API version 1.21). A flavor can request exactly one instance of a bare metal resource class.

Note that when creating the flavor, it’s useful to add the RAM_MB and CPU properties as a convenience to users, although they are not used for scheduling. The DISK_GB property is also not used for scheduling, but is still used to determine the root partition size.

  1. Change these to match your hardware:

    $ RAM_MB=1024
$ CPU=2
$ DISK_GB=100

  2. Create the bare metal flavor by executing the following command:

    $ openstack flavor create --ram $RAM_MB --vcpus $CPU --disk $DISK_GB \
  my-baremetal-flavor

    Note

    You can add --id <id> to specify an ID for the flavor.

See the docs on this command for other options that may be specified.

After creation, associate each flavor with one custom resource class. The name of a custom resource class that corresponds to a node’s resource class (in the Bare Metal service) is:

  • the bare metal node’s resource class all upper-cased

  • prefixed with CUSTOM_

  • all punctuation replaced with an underscore

For example, if the resource class is named baremetal-small, associate the flavor with this custom resource class via:

$ openstack flavor set --property resources:CUSTOM_BAREMETAL_SMALL=1 my-baremetal-flavor

Another set of flavor properties must be used to disable scheduling based on standard properties for a bare metal flavor:

$ openstack flavor set --property resources:VCPU=0 my-baremetal-flavor
$ openstack flavor set --property resources:MEMORY_MB=0 my-baremetal-flavor
$ openstack flavor set --property resources:DISK_GB=0 my-baremetal-flavor

Example

If you want to define a class of nodes called baremetal.with-GPU, start with tagging some nodes with it:

$ openstack --os-baremetal-api-version 1.21 baremetal node set $NODE_UUID \
  --resource-class baremetal.with-GPU

Warning

It is possible to add a resource class to active nodes, but it is not possible to replace an existing resource class on them.

Then you can update your flavor to request the resource class instead of the standard properties:

$ openstack flavor set --property resources:CUSTOM_BAREMETAL_WITH_GPU=1 my-baremetal-flavor
$ openstack flavor set --property resources:VCPU=0 my-baremetal-flavor
$ openstack flavor set --property resources:MEMORY_MB=0 my-baremetal-flavor
$ openstack flavor set --property resources:DISK_GB=0 my-baremetal-flavor

Note how baremetal.with-GPU in the node’s resource_class field becomes CUSTOM_BAREMETAL_WITH_GPU in the flavor’s properties.

Scheduling based on traits

Starting with the Queens release, the Compute service supports scheduling based on qualitative attributes using traits. Starting with Bare Metal REST API version 1.37, it is possible to assign a list of traits to each bare metal node. Traits assigned to a bare metal node will be assigned to the corresponding resource provider in the Compute service placement API.

When creating a flavor in the Compute service, required traits may be specified via flavor properties. The Compute service will then schedule instances only to bare metal nodes with all of the required traits.

Traits can be either standard or custom. Standard traits are listed in the os_traits library. Custom traits must meet the following requirements:

  • prefixed with CUSTOM_

  • contain only upper case characters A to Z, digits 0 to 9, or underscores

  • no longer than 255 characters in length

A bare metal node can have a maximum of 50 traits.

Example

To add the standard trait HW_CPU_X86_VMX and a custom trait CUSTOM_TRAIT1 to a node:

$ openstack --os-baremetal-api-version 1.37 baremetal node add trait \
  $NODE_UUID CUSTOM_TRAIT1 HW_CPU_X86_VMX

Then, update the flavor to require these traits:

$ openstack flavor set --property trait:CUSTOM_TRAIT1=required my-baremetal-flavor
$ openstack flavor set --property trait:HW_CPU_X86_VMX=required my-baremetal-flavor