Supported hardware

Metal3 supports many vendors and models of enterprise-grade hardware with a BMC (Baseboard Management Controller) that supports one of the remote management protocols described in this document. On top of that, one of the two boot methods must be supported:

1. Network boot. Most hardware supports booting a Linux kernel and initramfs via TFTP. Metal3 augments it with iPXE - a higher level network boot firmware with support for scripting and TCP-based protocols such as HTTP.

   Booting over network relies on DHCP and thus requires a provisioning network for isolated L2 traffic between the Metal3 control plane and the machines.

2. Virtual media boot. Some hardware model support directly booting an ISO 9660 image as a virtual CD device over HTTP(s). An important benefit of this approach is the ability to boot hardware over L3 networks, potentially without DHCP at all.

IPMI

IPMI is the oldest and by far the most widely available remote management protocol. Nearly all enterprise-grade hardware supports it. Its downside include reduced reliability and a weak security, especially if not configured properly.

WARNING: only network boot over iPXE is supported for IPMI.

Redfish and its variants

Redfish is a vendor-agnostic protocol for remote hardware management. It is based on HTTP(s) and JSON and thus does not suffer from the limitations of IPMI. It also exposes modern features such as virtual media boot, RAID management, firmware settings and updates.

Ironic (and thus Metal3) aims to support Redfish as closely to the standard as possible, with a few workarounds for known issues and explicit support for Dell iDRAC. Note, however, that all features are optional in Redfish, so you may encounter a Redfish-capable hardware that is not supported by Metal3. Furthermore, some features (such as virtual media boot) may require buying an additional license to function.

Since a Redfish API endpoint can manage several servers (systems in Redfish terminology), BMC addresses for Redfish-based drivers include a system ID - the URL of the particular server. For Dell machines it usually looks like /redfish/v1/Systems/System.Embedded.1, while other vendors may simply use /redfish/v1/Systems/1. Check the hardware documentation to find out which format is right for your machine.

Users have also reported success with certain models of SuperMicro, Lenovo, ZT Systems and Cisco UCS hardware, but hardware from these vendors is not regularly tested by the team.

All drivers based on Redfish allow optionally specifying the carrier protocol in the form of +http or +https, for example: redfish+http://... or idrac-virtualmedia+https. When not specified, HTTPS is used by default.

Redfish interoperability

As noted above, Redfish allows for very different valid implementations, some of which are not compatible with Ironic (and thus Metal3). The Ironic project publishes a Redfish interoperability profile – a JSON document that describes the required and optionally supported Redfish API features. Its available versions can be found in the Ironic source tree. The Redfish-Interop-Validator tool can be used to validate a server against this profile.

Check the Ironic interoperability documentation for a rendered version of the latest profile. All features required for Ironic are also required for Metal3. Most optional features except for the out-of-band inspection are also supported, although the hardware metrics support via ironic-prometheus-exporter is currently experimental and undocumented.

Vendor-specific protocols