Wake-On-Lan (WOL) power driver

https://blueprints.launchpad.net/ironic/+spec/wol-power-driver

This blueprint adds support for Wake-On-Lan (WOL) power interface in Ironic.

Problem description

Wake-On-Lan is a standard that allows a computer to be powered on by a network message. This is widely available and doesn’t require any fancy hardware to work with. This is useful for users that want to try Ironic with real bare metal instead of virtual machines and only have some old PCs around.

Proposed change

The proposed implementation consists of a driver power interface implementation that will create and send Wake-On-Lan magic packets for each port (MAC addresses) registered on the node resource in Ironic.

It’s important to note that Wake-On-Lan is only capable of powering on the machine. After the machine is unprovisioned it needs to powered off manually.

Driver properties that can be specified by the user::

wol_host: Broadcast IP address to send the magic packets. Defaults to 255.255.255.255.

wol_port: Destination port to send the magic packets; defaults to 9.

When powering off is called we are just going to log a message saying the operation isn’t supported by the driver and require manual intervention to be performed.

When reboot is called the driver will try to power on the machine.

When getting the power state of the node, the driver will rely on whatever is in the Ironic database and return it, since we don’t have any reliable way of knowing the current power state of the machine.

Alternatives

A alternative would be relying on some external mechanism to power control the nodes. Such as iBoot which Ironic already have a driver for. But for that the user will need to spend some money (~200 USD) to buy an iBoot device.

Data model impact

None

State Machine Impact

None

REST API impact

None

Client (CLI) impact

None

RPC API impact

None

Driver API impact

None

Nova driver impact

None

Security impact

This spec only covers the bits of sending a magic packet without the SecureOn feature.

SecureOn allows a client to append a password to the magic packet so NICs that support the feature will check prior to powering on the machine and if the MAC address + password are correct only then the system is awake . This is good against brute force attacks, but will be left for future work.

Other end user impact

None

Scalability impact

None

Performance Impact

None

Other deployer impact

None

Developer impact

None

Implementation

Assignee(s)

Primary assignee:
lucasagomes
Other contributors:
None

Work Items

  • Write the Wake-On-Lan power interface
  • Write unittests

Dependencies

None

Testing

Unittests will be added as part of the work.

Upgrades and Backwards Compatibility

None

Documentation Impact

The driver should be documented under http://docs.openstack.org/developer/ironic/index.html. The documentation will also be clear about the use of this driver, this is a testing driver and not meant for production use.