ironic/doc/source/install/include/boot-mode.rst

Boot mode support

The following drivers support setting of boot mode (Legacy BIOS or UEFI).

• pxe_ipmitool

The boot modes can be configured in Bare Metal service in the following way:

• When no boot mode setting is provided, these drivers default the boot_mode to Legacy BIOS.

• Only one boot mode (either uefi or bios) can be configured for the node.

• If the operator wants a node to boot always in uefi mode or bios mode, then they may use capabilities parameter within properties field of an bare metal node. The operator must manually set the appropriate boot mode on the bare metal node.

  To configure a node in uefi mode, then set capabilities as below:

  ironic node-update <node-uuid> add properties/capabilities='boot_mode:uefi'

  Nodes having boot_mode set to uefi may be requested by adding an extra_spec to the Compute service flavor:

  nova flavor-key ironic-test-3 set capabilities:boot_mode="uefi"
  nova boot --flavor ironic-test-3 --image test-image instance-1

  If capabilities is used in extra_spec as above, nova scheduler (ComputeCapabilitiesFilter) will match only bare metal nodes which have the boot_mode set appropriately in properties/capabilities. It will filter out rest of the nodes.

  The above facility for matching in the Compute service can be used in heterogeneous environments where there is a mix of uefi and bios machines, and operator wants to provide a choice to the user regarding boot modes. If the flavor doesn't contain boot_mode and boot_mode is configured for bare metal nodes, then nova scheduler will consider all nodes and user may get either bios or uefi machine.