ironic-inspector/doc/source/workflow.rst
Anton Arefiev 886d05ee64 Add fsm dot diagram generator
Add a tool which generates dot diagram from inspector state machine
using atomaton pydot convertor.

Also add generated svg diagram to docs.

Change-Id: I021812288f1833a6ebad2f90cbe862d40bd8d503
2017-03-01 14:46:28 +02:00

73 lines
2.9 KiB
ReStructuredText

Workflow
========
Usual hardware introspection flow is as follows:
* Operator enrolls nodes into Ironic_ e.g. via ironic CLI command.
Power management credentials should be provided to Ironic at this step.
* Nodes are put in the correct state for introspection as described in
:ref:`node_states`.
* Operator sends nodes on introspection using **ironic-inspector** API or CLI
(see :ref:`usage`).
* On receiving node UUID **ironic-inspector**:
* validates node power credentials, current power and provisioning states,
* allows firewall access to PXE boot service for the nodes,
* issues reboot command for the nodes, so that they boot the ramdisk.
* The ramdisk collects the required information and posts it back to
**ironic-inspector**.
* On receiving data from the ramdisk, **ironic-inspector**:
* validates received data,
* finds the node in Ironic database using it's BMC address (MAC address in
case of SSH driver),
* fills missing node properties with received data and creates missing ports.
.. note::
**ironic-inspector** is responsible to create Ironic ports for some or all
NIC's found on the node. **ironic-inspector** is also capable of
deleting ports that should not be present. There are two important
configuration options that affect this behavior: ``add_ports`` and
``keep_ports`` (please refer to ``example.conf`` for detailed explanation).
Default values as of **ironic-inspector** 1.1.0 are ``add_ports=pxe``,
``keep_ports=all``, which means that only one port will be added, which is
associated with NIC the ramdisk PXE booted from. No ports will be deleted.
This setting ensures that deploying on introspected nodes will succeed
despite `Ironic bug 1405131
<https://bugs.launchpad.net/ironic/+bug/1405131>`_.
Ironic inspection feature by default requires different settings:
``add_ports=all``, ``keep_ports=present``, which means that ports will be
created for all detected NIC's, and all other ports will be deleted.
Refer to the `Ironic inspection documentation`_ for details.
* Separate API (see :ref:`usage` and :ref:`api`) can be used to query
introspection results for a given node.
* Nodes are put in the correct state for deploying as described in
:ref:`node_states`.
Starting DHCP server and configuring PXE boot environment is not part of this
package and should be done separately.
State machine diagram
=====================
The diagram below shows the introspection states that an **ironic-inspector**
FSM goes through during the node introspection, discovery and reprocessing.
The diagram also shows events that trigger state transitions.
.. figure:: ./images/states.svg
:width: 660px
:align: center
:alt: ironic-inspector state machine diagram
.. _Ironic inspection documentation: http://docs.openstack.org/developer/ironic/deploy/install-guide.html#hardware-inspection
.. _Ironic: https://wiki.openstack.org/wiki/Ironic