a5f7d75ba2
For some (likely historical) reasons we only use it for PXE and iPXE, but the same logic applies to any boot interface (since it depends on how the management interface and the BMC work, not on the boot method). This change moves its handling to conductor utils. Change-Id: I948beb4053034d3c1b4c5b7c64100e41f6022739
2.6 KiB
Boot interfaces
The boot interface manages booting of both the deploy ramdisk and the user instances on the bare metal node.
The PXE boot interface is generic and works
with all hardware that supports booting from network. Alternatively,
several vendors provide virtual media implementations of the
boot interface. They work by pushing an ISO image to the node's management
controller, and do not require either PXE or iPXE. Check your driver
documentation at ../drivers for details.
PXE boot
The pxe boot interface uses PXE
or iPXE to deliver the
target kernel/ramdisk pair. PXE uses relatively slow and unreliable TFTP
protocol for transfer, while iPXE uses HTTP. The downside of iPXE is
that it's less common, and usually requires bootstrapping using PXE
first.
The pxe boot interface works by preparing a PXE/iPXE
environment for a node on the file system, then instructing the DHCP
provider (for example, the Networking service) to boot the node from it.
See iscsi-deploy-example and direct-deploy-example for a
better understanding of the whole deployment process.
Note
Both PXE and iPXE are configured differently, when UEFI boot is used instead of conventional BIOS boot. This is particularly important for CPU architectures that do not have BIOS support at all.
The pxe boot interface is used by default for many
hardware types, including ipmi. Some hardware types,
notably ilo and irmc have their specific
implementations of the PXE boot interface.
Additional configuration is required for this boot interface - see
/install/configure-pxe
for details.
Common options
Enable persistent boot device for deploy/clean operation
Ironic uses non-persistent boot for cleaning/deploying phases as default. For some drivers, a persistent change is far more costly than a non-persistent one, so this can bring performance improvements.
Set the flag force_persistent_boot_device to
True in the node's driver_info:
$ baremetal node set --driver-info force_persistent_boot_device=True <node>Note
It's recommended to check if the node's state has not changed as there is no way of locking the node between these commands.
Once the flag is present, the next cleaning and deploy steps will be done with persistent boot for that node.