Note
The term disk label
is historically used in Ironic and was taken
from parted. Apparently
everyone seems to have a different word for disk label
- these
are all the same thing: disk type, partition table, partition map
and so on…
Ironic allows operators to choose which disk label they want their
bare metal node to be deployed with when Ironic is responsible for
partitioning the disk; therefore choosing the disk label does not apply
when the image being deployed is a whole disk image
.
There are some edge cases where someone may want to choose a specific disk label for the images being deployed, including but not limited to:
bios
boot mode with disks larger than 2 terabytes
it’s recommended to use a gpt
disk label. That’s because
a capacity beyond 2 terabytes is not addressable by using the
MBR partitioning type. But, although GPT claims to be backward
compatible with legacy BIOS systems that’s not always the case.uefi
) to avoid breakage
of applications and tools running on those instances.The disk label can be configured in two ways; when Ironic is used with the Compute service or in standalone mode. The following bullet points and sections will describe both methods:
bios
boot mode will use
msdos
and uefi
boot mode will use gpt
.msdos
or gpt
- can be configured
for the node.When Ironic is used with the Compute service the disk label should be
set to node’s properties/capabilities
field and also to the flavor
which will request such capability, for example:
ironic node-update <node-uuid> add properties/capabilities='disk_label:gpt'
As for the flavor:
nova flavor-key baremetal set capabilities:disk_label="gpt"
When used without the Compute service, the disk label should be set
directly to the node’s instance_info
field, as below:
ironic node-update <node-uuid> add instance_info/capabilities='{"disk_label": "gpt"}'
Except where otherwise noted, this document is licensed under Creative Commons Attribution 3.0 License. See all OpenStack Legal Documents.