diff --git a/doc/source/admin/useful-image-properties.rst b/doc/source/admin/useful-image-properties.rst index 8c997fd276..ca730bf2dc 100644 --- a/doc/source/admin/useful-image-properties.rst +++ b/doc/source/admin/useful-image-properties.rst @@ -230,6 +230,32 @@ Here is a list of useful image properties and the values they expect. - The ID of image stored in the Image service that should be used as the ramdisk when booting an AMI-style image. - Valid image ID. + * - All + - ``trait:`` + - Added in the Rocky release. Functionality is similar to traits specified + in `flavor extra specs `_. + + Traits allow specifying a server to build on a compute node with the set + of traits specified in the image. The traits are associated with the + resource provider that represents the compute node in the Placement API. + + The syntax of specifying traits is **trait:=value**, for + example: + + * trait:HW_CPU_X86_AVX2=required + * trait:STORAGE_DISK_SSD=required + + The nova scheduler will pass required traits specified on the image to + the Placement API to include only resource providers that can satisfy + the required traits. Traits for the resource providers can be managed + using the `osc-placement plugin. `_ + + Image traits are used by the nova scheduler even in cases of volume + backed instances, if the volume source is an image with traits. + - Only valid value is ``required``, any other value is invalid. + + * ``required`` - is required on the resource provider that + represents the compute node on which the image is launched. * - All - ``vm_mode`` - The virtual machine mode. This represents the host/guest ABI