OPMA

Open Platform Management Architecture (OPMA) is an open, royalty free standard for connecting a modular, platform hardware management subsystem (an "mCard") to a computer motherboard. Platform hardware management generally refers to the remote monitoring of platform hardware variables such as fan speed, voltages, CPU and enclosure temperatures along with a wide range of other sensors. It also implies the ability to remotely control the power state of the platform and to reset the system back into an operational state should it "hang". A significant advantage of OPMA over previous generation management subsystem attachment methods is that OPMA does not consume a PCI socket. OPMA cards are also smaller and lower cost than their PCI predecessors.

The OPMA specification, which can be freely downloaded from the web, specifies a signal list, connector and pin out, power requirements, mechanical form factor, BIOS and management controller firmware interfaces, and a detailed division of management subsystem resources between the motherboard and the mCard. OPMA enables a wide variety of mCards to individually interface to a given motherboard. It also enables a single mCard to individually interface to multiple motherboard models.

OPMA is mainly targeted at server platforms where the cost of a card based management subsystem is more easily borne, but high end workstations may also leverage the specification to handle cases where remote workstation platform management is required. The OPMA interface is flexible enough to handle multiple mCard price points and capabilities ranging from basic IPMI based management to those that support KVMoIP, remote virtual media, and newer external interface standards that require a larger on-card resource footprint such as WS-Management.

OPMA supports two basic management subsystem connection paradigms. The first is where virtually the entire management subsystem resides on the mCard. Using this paradigm, the platform contains no basic management controller of any sort and relies on the presence of an OPMA card for all remote hardware management capabilities. In the second paradigm, the basic management module is soldered to the motherboard and the OPMA connector is used as an upgrade path for advanced platform management features. In this case, which is known as "upgrade kit mode", the OPMA card is able to access all sensors supported by the soldered down management controller using an SMBus link over which the Intelligent Platform Management Bus (IPMB) protocol is employed.

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Wikipedia