ironic/doc/source/admin/interfaces/deploy.rst

Deploy Interfaces

A deploy interface plays a critical role in the provisioning process. It orchestrates the whole deployment and defines how the image gets transferred to the target disk.

iSCSI deploy

With iscsi deploy interface (and also oneview-iscsi, specific to the oneview hardware type) the deploy ramdisk publishes the node's hard drive as an iSCSI share. The ironic-conductor then copies the image to this share. See iSCSI deploy diagram <iscsi-deploy-example> for a detailed explanation of how this deploy interface works.

This interface is used by default, if enabled (see enable-hardware-interfaces). You can specify it explicitly when creating or updating a node:

openstack baremetal node create --driver ipmi --deploy-interface iscsi
openstack baremetal node set <NODE> --deploy-interface iscsi

The iscsi deploy interface is also used in all of the classic drivers with names starting with pxe_ (except for pxe_agent_cimc) and iscsi_.

Direct deploy

With direct deploy interface (and also oneview-direct, specific to the oneview hardware type), the deploy ramdisk fetches the image from an HTTP location. It can be an object storage (swift or RadosGW) temporary URL or a user-provided HTTP URL. The deploy ramdisk then copies the image to the target disk. See direct deploy diagram <direct-deploy-example> for a detailed explanation of how this deploy interface works.

You can specify this deploy interface when creating or updating a node:

openstack baremetal node create --driver ipmi --deploy-interface direct
openstack baremetal node set <NODE> --deploy-interface direct

The direct deploy interface is also used in all classic drivers whose names include agent.

Note

For historical reasons the direct deploy interface is sometimes called agent, and some classic drivers using it are called agent_*. This is because before the Kilo release ironic-python-agent used to only support this deploy interface.

Ansible deploy

This interface is similar to direct in the sense that the image is downloaded by the ramdisk directly from the image store (not from ironic-conductor host), but the logic of provisioning the node is held in a set of Ansible playbooks that are applied by the ironic-conductor service handling the node. While somewhat more complex to set up, this deploy interface provides greater flexibility in terms of advanced node preparation during provisioning.

This interface is supported by most but not all hardware types declared in ironic (for example, oneview hardware type does not support it). However this deploy interface is not enabled by default. To enable it, add ansible to the list of enabled deploy interfaces in enabled_deploy_interfaces option in the [DEFAULT] section of ironic's configuration file:

[DEFAULT]
...
enabled_deploy_interfaces = iscsi,direct,ansible
...

Once enabled, you can specify this deploy interface when creating or updating a node:

openstack baremetal node create --driver ipmi --deploy-interface ansible
openstack baremetal node set <NODE> --deploy-interface ansible

For more information about this deploy interface, its features and how to use it, see Ansible deploy interface <../drivers/ansible>.

../drivers/ansible